Question

An electrician needs 3 1/4 rolls of electrical wire to wire each room in a house. How many rooms can he wire with 9 1/4 rolls of wire

Answer 1

Number of rooms can be wired by electrician is approximately 3

Solution:

Given that electrician needs
`3(1)/(4)` rolls of electrical wire to wire each room in a house

To find: number of rooms can he wire with
`9(1)/(4)` rolls of wire

From given information,

Rolls of wire needed for 1 room =
`3(1)/(4) = (4 * 3 + 1)/(4) = (13)/(4)`

Total rolls of wire =
`9(1)/(4) = (4 * 9 + 1)/(4) = (37)/(4)`

So number of rooms can be wired:

`\text{ number of rooms }=\frac{\text{ total rolls of wire}}{\text{ wire needed for 1 room}}`

`\text{ number of rooms } = ((37)/(4))/((13)/(4)) = (37)/(4) * (4)/(13) = (37)/(13)`

`\rightarrow(37)/(13) = 2.84 \approx 3`

Thus number of rooms can be wired is
`(37)/(13)` or approximately 3 rooms