Decimal Fractions Examples

In this class, We discuss Decimal Fractions Examples.

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The reader should have prior knowledge of decimal fraction division and multiplication. Click Here.

Example 1:

A tailor has 37.5 meters of cloth. He has to make 8 pieces out of a meter of cloth.

How many pieces can he make out of his cloth?

Solution:

The length of each piece is 1/8 of a meter = 0.125 m

Required number of pieces = Total cloth length / each piece length

Number of pieces = 37.5/0.125

Decimal fraction divided by decimal fraction.

We discussed the division of decimal fractions in our previous classes.

(37.5 * 1000)/ (0.125 * 1000) = 300

Number of pieces = 300

Example 2:

The price of commodity x increases by 40 paise yearly, while the price of commodity y increases by 15 paise yearly.

In 2001 the price of commodity x was Rs 4.20, and y was Rs 6.30.

In which year will commodity x cost 40 paise more than commodity y?

Solution:

Suppose commodity x will cost 40 paise more than commodity y after z years.

(4.20 + 0.40z) – (6.30 + 0.15z) = 0.40

0.25z = 0.40 + 2.10

z = 2.50/0.25 = 10

z = 10

After ten years, x cross y by 0.40 paise.

Example 3:

The sum of the first 20 terms of the series

(1/(5*6)) + (1/(6*7)) + (1/(7*8)) . . . .

We write the series as

(1/5 – 1/6) + (1/6 – 1/7) + . . .

Cancel negative and positive terms

= (1/5 – 1/25)

= 4/25 = 0.16