Question

the standard bag is 21in wide at the base. what scale factor is needed to make a bag with a base width of 7in

Answer 1

Dividing 21 by 7 will give to the proportion of 1:3 which is your scale for the bag with the 7inch base

Answer 2

Scale factor =
`(1)/(3)`

Explanation:

In the figure attached, there are two bags. Larger one with the base of 21 in wide and another bag with a base of 7 in wide.

Since both the bags are similar in their shape.

Scale factor by which the smaller bag can be formed will be =
`\frac{\text{Base length of the smallerer bag}}{\text{Base length of the larger bag}}`

=
`(7)/(21)`

=
`(1)/(3)`

Therefore, by multiplying every side of the larger bag with the scale factor
`(1)/(3)` we can get the dimensions of the smaller one.