Question

The diameter of a strand of rope is 1.2 × inch. The diameter of a strand of floss is 2.0 × inch. How much longer is the diameter of the strand of rope than the diameter of the strand of floss

A. 2.0 x 10^-7

B. 1.0 x 10^-7

C. 2.0 x 10^-3

D. 1.0 x 10^-3

Answer 1

Option D
`1*10^(-3)\ in`

Explanation:

The correct question is

The diameter of a strand of rope is 1.2x10^-3 inch. the diameter of a strand of floss is 2.0x10^-4 inch. how much longer is the diameter of the strand of rope than the diameter of the strand of floss?

we know that

To find out how much longer is the diameter of the strand of rope than the diameter of the strand of floss, subtract the diameter of the strand of floss from the diameter of the strand of rope

so

`1.2*10^(-3)-2*10^(-4)`

Remember that

`1.2*10^(-3)=12*10^(-4)`

Because

`1.2*10^(-3)=1.2*10^(-3)(10^(-1))/(10^(-1))=1.2*10^(-4)(10)=12*10^(-4)`

substitute in the expression above

`12*10^(-4)-2*10^(-4)=10*10^(-4)\ in=1*10^(-3)\ in`