Detailed Lesson Plan 1

A DETAILED LESSON PLAN IN MATHEMATICS FOR GRADE-FOUR I.

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OBJECTIVES At the end of a 45-minute period, the grade four pupils will be able to: 1. Add and subtract fractions with the same denominators, 2. Add and subtract fractions with dissimilar denominators, 3. Add and subtract mixed numbers with similar denominators, and 4. Add and subtract mixed numbers with dissimilar denominators with 75% proficiency level. SUBJECT MATTER ADDING AND SUBTRACTING OF FRACTIONS A. References Liking Mathematics in the Grade School: Textbook in Mathematics for Grade-Four by Prepotente et.al. 21st Century Mathematics (6) by Villame et.al. B. Materials Power point presentation, visual aids C. Ideas To add/subtract fractions with similar denominators, we add/subtract the numerator and write the sum/difference over the same denominator. To add/subtract fractions with dissimilar denominators, first find the smallest equivalent fractions by using the least common multiple (LCD) to rename the dissimilar fractions into similar fractions and then proceed as in adding/subtracting fractions with the same denominator. To add/subtract mixed numbers with similar denominators, we add/subtract the whole numbers, then the numerators and retain the denominator. To add/subtract mixed numbers with dissimilar denominators, change dissimilar fractions to similar fractions. Add/subtract the whole numbers, and then the numerators and copy the denominator. D. Processes Identifying, adding, subtracting E. Value Small parts are necessary to make-up a whole. PROCEDURE A. Pre-assessment 1.Prayer 2.Checking of attendance 3.Review of the past lesson B. Motivation A song about mathemetics C. Lesson proper Teacher Activity Pupil Activity Class, do you love to eat chocolates? Yes Ma’am Who wants to eat a chocolate? We’d love to, Ma’am. I have here a bar of chocolate and I am going to divide it equally into four parts. (Slice). So I have now 4 slices or 4/4 of chocolate. (Give the 2/4 of the apple to two pupils, 1/4 each). So I have given Mario ¼ of the chocolate and another ¼ to Rowena. How much chocolate have I given all in all and how 2/4 given much is left? 2/4 left Yes Very Good! I sliced the chocolate into fourequal parts so we get 4/4 or 1 of course and I gave Mario and Rowena ¼ each of the chocolate. So ¼ + ¼ , we get 2/4 or ½ and the parts that is left for me is also 2/4 0r ½ . If we are going to add the parts of apple that I have given to Mario and Rowena

and the parts left for me, how much will it be all in all? Now class, do you have any idea of what will be our topic for today? Exactly class. Today, we will be discussing how to add and subtract fractions. And I want you to meet the following objectives which are to: add and subtract fractions with the same denominators, add and subtract fractions with dissimilar denominators, add and subtract mixed numbers with similar denominators, and add and subtract mixed numbers with dissimilar denominators with 75% proficiency level. Can I expect that from you? So we have here different rules in adding and subtracting of fractions. Take note that I am going to give you a quiz after this so you better bear with me class, listen carefully as I am going to present and discuss each rule one after the other. To add fractions with similar denominators,we simply add the numerators andwrite the sum over the same denominator. Dulce ate ⅖ of the cake in the morning and ⅕ in the afternoon. How much cake was eaten by her? What is asked in the problem? What are given? So we are going to add the given fractions to answer what is asked in the problem. As what is stated in the rule, we simply add the numerators and write the sum over the same denominator in adding of similar fractions. So we simply add 2 and 1 which is equal to 3 and write it over the same denominator which is 5. And the answer is 3/5. Did you get it? So let’s proceed. To subtract fractions with similar denominators, we simply subtract the numerators and write the difference over the same denominator. This is somewhat similar as in adding of fractions with similar denominators. The only difference is we are going to subtract the numerators instead of adding A water tank was ⅞ full of water. After a day of use, it was ⅜ full. How much water was used during the day? What is asked? What are given?

4/4 or 1 Adding and subtracting of fraction

Sure Ma’am.

The amount of cake eaten by Dulce. 2/5 cake in the morning and 1/5 in the afternoon.

Yes Ma’am.

The amount of water that was used during the day. 7/8 full of water and 3/8 full after a day of use.

To find the amount of water that was used during the day, we are going to subtract 3/8 from 7/8. So simply subtract the numerators 7-3 is equal to 4 and write it over the same denominator which is 8 and then we get 5/8. To add fractions with dissimilar denominators, rename the dissimilar fractions into similar fractions by finding the (LCD) and then proceed as in adding fractions with the same denominator. Mother used ⅗ liter of cooking oil last month and⅔ liter this month. How much did she use in two months? What is asked? What are given?

The amount of cooking oil mother used in two months. 3/5 liter of cooking oil last month and 2/3 liter this month.

How do we add 3/5 and 2/3? Examine their denominators. Do they have the same or what? Obviously! So the first we need to find The LCD or (Least Common Denominator). What is the LCD of 5 and 3? Aha! And we are going to use 15 to rename these dissimilar fractions into similar fractions. And then we get 9/15 and 10/15 so we can now add these similar fractions to get the answer which is 19/15 or 1 4/15. To subtract fractions with dissimilar denominators, rename the dissimilar fractions into similar fractions by finding the (LCD) and then proceed as in subtracting fractions with the same denominator. Aling Dionisia, a stuffed-toy maker, uses 5/9 bag of stuff for a dog and 4/6 bag of stuff for a cat. How much more stuff does she use for a dog than for a cat. What is asked? What are given? Like adding of fractions with dissimilar denominators, we need To find the LCD in order to rename these fractions into similar fractions allowing us to proceed in subtraction. What is the LCD of 6 and 9? So the fractions involved are now 12/18 and 10/18. And to answer what is asked in the problem we are going to subtract 10/18 from 12/18 and we get 2/18 or 1/9. . To add mixed numbers with similar denominators, we add the whole numbers,then the numerators and retain

Different/dissimilar 15

The amount of stuff she use for a dog than for a cat. 4/6 bag of stuff for dog and 5/9 bag of stuff for a cat.

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the denominator. What do you mean by mixed numbers? Yes, exactly! We have discussed that already. Jebs and Brion helped in the “Operation Linis” on Saturday and Sunday. John mowed 3⅓ of the lawn and Bob mowed 4⅓ of it .What part of the lawn did the two boys mow together? What is asked? What are given? 3⅓ and 4⅓ are examples of mixed numbers with similar denominators of which we can just add directly without the need of finding an LCD. We automatically add the whole numbers3+4=7 and then the numerators- 1+1=2 and write it over the same denominator- 3. The part of the lawn the two boys mowed together is 7 2/3. To subtract mixed numbers with similar denominators, we subtract the whole numbers, then the numerators and retain the denominator. A vendor sold 316/7 kilograms of mangoes on Monday and 26 5/7 kilograms on Tuesday. How much more kilograms of mangoes did she sell on Monday than on Tuesday? What is asked?

What are given? As stated in the rule we are going to subtract first the whole numbers31-26=5, and then the numerators6-5=1 and write it over the same denominator 7. And we get the answer which is 5 1/7. To add mixed numbers with dissimilar denominators, change dissimilar fractions to similar fractions. Add the whole numbers, and then the numerators, and copy the denominator. Vener and Edmund opened a vegetable stand in a supermarket. On opening day, they sold 4 5/8 bushels of corn and sold 3 4/6 bushels on the following day. How much corn was sold in two days? What is asked? What are given?

A mixed number is composed of a whole number and a fraction.

The part of the lawn the two boys mow together. John mowed 3⅓ of the lawn and Bob mowed 4⅓ of it.

The amount of mangoes in kls that she sell more on Monday than on Tuesday. 31 6/7kls of mangoes on Monday and 26 5/7 kls on Tuesday.

The amount of corn that was sold for two days. On opening day, they sold 4 5/8 bushels of corn and sold 3 4/6 bushels on the following day

How are we going to change dissimilar fractions into similar fractions? Precisely! And what is the LCD of 8 and 6? Through obtaining the LCD of dissimilar fractions, we can derived its similar fractions and then perform the indicated operation. 4 5/8 and 3 4/6 = 4 30/8 and 3 24/8. When added, 4+3=7(whole numbers) and 54/8 (similar fractions) we get 7 54/8. To subtract mixed numbers with dissimilar denominators, change dissimilar fractions to similar fractions. Subtract the whole numbers, and then the numerators, and copy the denominator. Mang Tony is a candle maker. He had 5 3/4 disks of wax. He used 4 2/5 of them. How much wax does he have left? What is asked? What are given?

find the LCD 48

The amount of wax he have left. He had 5 2/5 disks of wax and he used 4 3/4 of them.

What is the LCD of 4 and 5? 20 Through the use of LCD we can now derived similar fractions where we can apply operations directly. In this case the fractions that we derived are 5 15/20 and 4 8/20. Subtract the whole numbers- 5-4=1 and then the numerators15-8=7 and write it over the same denominator 20. The answer is 1 7/20. Deductive Method IV. EVALUATION Direction: Solve each problem. 1. Julie bought ½ meter of red ramie cloth for her table napkins and 3/6 white ramie cloth for placemats. How many meters of cloth did she buy? 2. Mrs. Robles baked 1⅔ dozen cookies. She brought ¾ dozen to school for her friends. How many dozen of cookies were left? V. ASSIGNMENT Direction: Perform the indicated operation. a. 1 2/5+3/5 b. 2 ¼ - 2/4 c. 1-6/6