Question

State true or False.
The weight of 80 identical books is 400 kg. Then weight of one such book is 5 kg..

Answer 1

True
Given:
Weight of 80 identical books = 400 kg

Using unitary method, we get,
Weight of 1 book
$=\frac{400}{80}=\frac{10\times 40}{10\times 8}=\frac{40}{8}=5$

Therefore, weight of 1 such book is 5 kg.