Question

A family uses three 100W bulbs for 5 hours daily, calculate energy consumed in 20 days.​

Answer 1

Solution:

The family uses three 100 w bulbs in = 5 hours

They use in 1 hour

$= \frac{100}{5} \: w \\ = 20 \: w$

They use in 24 hours or 1 day

$= (20 \times 24) \: w \\ = 480 \: w$

They use in 20 days

$= (480 \times 20) \: w \\ = 9600 \: w$

∴ The family uses 9600 w in 20 days.

Answer 2

The family uses three 100W bulbs = 5 hours daily.

They use in 1 hour = (100 ÷ 5)W

= 20

They use in 1 day = (20×24)W

= 480W

They use in 20 days = (480×20)W

= 9600W

∴The family use 9600W in 20 days.