Money: Introduction

Introduction

To learn to use Operations to find totals, change, multiple costs and unit cost.

Panneerselvam and his three friends went to seashore. They played and took rest. By that time they bought 4 packets of cereals from the seller for ₹ 20. Panneer does not know the cost of one packet then he asked his friend.

His friend explained him to find out the cost.

4 packets of cereals = ₹ 20

∴ 1 packet of cereals = ₹ 20 ÷ 4

So, 1 packet of cereals = ₹ 5.

Panneer and his friends have eaten cereals and went to a tea shop. The price of tea was 5 rupees. Panneer and his friends drunk tea and gave ₹ 20 to the seller.

Panneer does not know the total cost of tea. He asked his friend to explain him,

Cost of one tea = ₹ 5

Cost of four tea = ₹ 5 × 4

Cost of four tea = ₹ 20

Let us try

Find the cost per item, if the total cost is given. One is done for you.

Fill in the following:

Panneer and his friends spent the amount for cereals ₹ 20 and another for tea ₹ 20. Also they spent ₹ 40 for horse – riding. They went home happily. After he went home he calculated the amount left in ₹ 100.

Let us help Panneer,

Cost of cereals                                 = ₹ 20 +

Cost of tea                                        = ₹ 20

The amount spent for horse – riding  = ₹ 40

Total expenditure                              = ₹ 80

Total amount with Panneer                          = ₹ 100

Amount Spent by Panneer and his friends   = − ₹ 80

Balance amount                                           = ₹ 20

Activity

1. Make the students to form a model market to display the price list of the things to learn addition and subtraction. 

2. Write the value of currency in the paper, make a student to act like a shopkeeper and the other students are like customer, calculate the cost of things to learn addition and subtraction.

EXAMPLE 1

Nandhakumar spent the amount of ₹ 750 for 10 l petrol. What is the cost of 1 l petrol.

Nandhakumar spent the amount for petrol = ₹ 750

∴ Cost for 1 l petrol = ₹ 750 ÷ 10

 = ₹ 75

EXAMPLE 2

Madhumitha bought 8 sweet packets. If one packet costs ₹ 65, find the cost of 8 packets.

Cost of one packet = ₹ 65

∴ Cost of eight packets = ₹ 65 × 8

∴ Cost of eight packets = ₹ 520

EXAMPLE 3

Selvam went to vegetable market and bought onion for ₹ 10.50 and cucumber for ₹ 8.75. If he has given ₹ 20 to the shopkeeper then find the balance amount received by selvam.

Cost of onion                                 = ₹ 10.50

∴ Cost of cucumber                       = ₹ 8.75

The amount spent for vegetables = ₹ 19.25 

The amount given to the shopkeeper    = ₹ 20.00

The amount spent for vegetables         = ₹ 19.25

Balance amount                                    = ₹ 0.75