Question

In a bookshop ,204 copies of a certain book require shelf length of 5.1 meter . how many copies of the same book would occupy a shelf length of 3.4 meter​

Answer 1

Answer:

136 copies of the same book would occupy a shelf length of 3.4 meter

Step-by-step explanation:

We can solve this using 2 methods, here we go

Method 1 (Unitary method)

Considering that the books are kept on top of each other,

204 copies of a certain book requires a shelf length of 5.1 m

Then,

1 m of shelf length will have 204/5.1 = 40 copies

Then,

3.4 m shelf length will have 40 × 3.4 = 136 copies

Method 2 (Proportionality method)

We know that,

Considering that the books are kept on top of each other,

204 copies of a certain book requires a shelf length of 5.1 m

The books must have equal width,

Thus, they are proportional,

Let the number of books be x

204/5.1 = x/3.4

Cross multiplying we get,

5.1 × x = 204 × 3.4

5.1x = 693.6

x = 693.6/5.1

x = 136 copies

OR

204 : 5.1 :: x : 3.4

We know that,

Product of extremes = product of means

204 × 3.4 = 5.1 × x

5.1x = 693.6

x = 693.6/5.1

x = 136 copies

Thus, 136 copies of the same book would occupy a shelf length of 3.4 meter

Hope it helped and you understood it........All the best