Question

The scale factor on a scale drawing of machine part is 15 1 /8. If the part is 3 7/8 inches long as the drawing, how long is the actual part?
A)3 28/31 inches
B)11 1/4 inches
C)19inches
D) 58 39/64 inches​

Answer 1

Answer:

Option D) 58 39/64 inches​

Step-by-step explanation:

we know that

The scale drawing is

$15\frac{1}{8}$

convert to an improper fraction

$15\frac{1}{8}=\frac{15*8+1}{8}=\frac{121}{8}$

That means

121 in in the actual, represent 8 in on a scale drawing

To find how long is the actual part for 3 7/8 inches long as the drawing

Apply proportion

First convert to an improper fraction

$3\frac{7}{8}=\frac{3*8+7}{8}=\frac{31}{8}$

$\frac{121}{8}\frac{actual}{drawing} =\frac{x}{(31/8)}\frac{actual}{drawing}\\ \\x=121(31/8)/8\\ \\x=\frac{3,751}{64}\ in$  

convert to mixed number

$\frac{3,751}{64}\ in=\frac{3,712}{64} +\frac{39}{64} =58\frac{39}{64}\ in$