Number of books = 42 / 5/8 (Note 3 1/2 feet = 42 ins.)
= 42 * 8/5 = 336 / 5 = 67.2
67 books will fit on the shelf.
Number of cubes increases by 3 for each term.
an= 3n+1
50% is

We have two ways to do this, pick your favor:
either by fractions:

÷

(

Multiply by the reciprocal of

which is 2(flip it)

× 2 =
= 1.25
Or change them to decimals:


= 0.5
0.625 ÷ 0.5
0.5 I 0.625
multiply by 10 to make it easier to divide(it still gives us the same answer)
0.5 × 10 = 5
0.625 × 10 = 6.25
1.25
5 I 6.25
-5
12
-10
25
-25
0
0.625 ÷ 0.5 =
1.25