Students’ Learning Outcomes
· Describe the concept of unitary method
· Calculate the value of many objects of the same kind when the value of one of these objects is given
· Calculate the value of a number of same types of objects when the value of another of the same type is given(unitary method)
Information for Teacher
In unitary method we dear with the following:
· Finding the price of more things when price of one thing is given
· Finding the price of 1 thing if price of more things is given
· Finding the price of given number of things if the price of other number of same things is given
· During lesson where and when necessary also consult text
Material / Resources
Prepare question slips for application of unitary method, chart paper
Worm up activity
Unitary method considers the example:
· 9 meters of cloth cost PRs 540, what will be the cost of 4 meters?
· Here cost of 9 meters cloth is given. This part of question is called a statement
· From this, value of 1 meter is to be obtained by compound division and from this value of 1 meter the cost of 4 meters is obtained by compound multiplication
· This method in which the value of a unit is first found is called unitary method or method of reduction to the unit
· Tell the students that unitary method has several uses in our daily life like when we talk about speed, rate or percentage, we invariably relate to unitary method
· Announce that today we will explore about unitary method in detail
· Write “unitary method” in the middle of the board
· Ask the class what do they know about unitary method?
· Write their responses on board, appreciate closer or correct answer
· In the word unitary encircle unit and say that unit means one
· If we know the relation of one unit value with more values we can find the relation of any value with any other numbers
· Write the question on the board “if 1 dollar is equal to PRs. 102” then what is the value of 10 dollars?
· Let them think and come up with the answer 84 x 10 = 840
· Tell them that as we got the value of one dollar we were able to find the value of 10 dollars
· Tell the students that in the same way if we are given value of certain objects/things we can find the value of other number or quantity of the same object/thing
· Tell the students like a story. I bought 30 bananas and paid PRs 150. When I reached home my mother asked me to get 20 more bananas. How much I would pay for 20 bananas?
· How many bananas I bought? 
· How much I paid for that ?
· To pay for 20 bananas what do I need to know? [Rate or cost of 1 bananas]
· How would I know the rate of the bananas ?[by using unitary method]
o Cost of 1 banana = 150 /30 = PRs 3
o What is the cost of 20 bananas? 20 x 3 = PRs 60.00
· Ask students following questions and tell them to tell you what do they need to get the answer:
o 20 apples cost PRs 130, what will 15 apples cost?
o Car travels 120 km in 8 liters, how much it will travel in 10 liters
o A machine fills 200 bottles in 5 minutes, how many it will in 7 minutes?
· Appreciate the correct work and encourage students to give more examples of the same kind
· Select few questions from the textbook exercise and give as individual work to do in their notebooks
· Ask volunteer students to explain in their own words telling how unitary method is used to solve the following questions:
o Petrol is PRs 80 per liter, I got my bike filled with 3 liters, tell how much did I pay?
o One juice cost PRs 12. You have 5 friends with you, how much will pay for 5 juices?
o One color marker is of 8 rupees, what will be the cost of 10 markers?
· Ask similar type of question to reinforce that it’s easy to find the value of two or more objects when the value of one object is given
· After students explain the questions refer them in pairs to the textbook selected questions to solve in their notebooks
· Keep roaming in the class while students are doing their work, correct them if they make any mistake
· Divide the class into groups of 4 or 5
· Select one group leader and assign him/her to explain unitary method to each of your group member. Allocate 97 minutes)
· Working in the same groups, develop 5 questions which can be solved with unitary method
· Prepare question slips, also ask them to write their group number at the back of their sheets
· Collect all slips and put them in a box to shuffle
· Prepare some questions yourself as well and put those in the box too
· Ask each group to take slips according to the members of the group
· Read the statements and identify wrong statements
· Solve the correct questions
· Paste the slips on a chart paper and display in classroom
· Turn by turn call groups and ask them to explain in the work
· Appreciate for correct work and make corrections in wrong answers and questions
Sum up / Conclusion
· Lesson will be concluded by recapping following points:
o How to find unit cost if cost of more items is given?
o What will you do if you are given the cost of 15 items and you have to find the cost of one item?
o State the operation done if you are given the cost of 15 items and you have to find the cost of 18 items?
o What is the use of unitary method in daily life?
· Call three students on the board and give them names of alphabets “A, B and C”. tell them to remember their names
· Allocate time 5 minutes
· Attempt following questions according to their alphabet
I. A factory can make 36 toy cars in six hours. How many can it make in:
a) 1 hour?
b) 5 hours?
c) 1 day?
II. A building company can lay 375 brick in 3 hours. How many brick can they lay in
a) 1 hour?
b) 5 hours?
c) 12 hours?
III. 6 story books cost a total of PRs 480. What is the cost of:
a) One book
b) Eight books
c) Ten books
· Assign practice questions from the textbook
· Ask them to create two story problems to be shared in the next class in which unitary methods is to be applied