Rayna is building a tapered staircase using wooden boards. The bottom stair is 3 ft wide, and the top stair is 2 ft wide. Each stair is 4 in.

shorter than the one below. What is the total length of wooden boards Rayna needs for the stair tops, in feet? Enter your answer in the box as

an improper fraction.

Total length of wooden boards = 10 feet

As 10 is a whole number, it can't be written as an improper fraction.

Step-by-step explanation:

First we need to convert the 4 in measurement to foot.

The conversion rate is: 12 inches = 1 foot.

So we have that 4 inches is equal to 1/3 feet.

If each stair is (1/3) feet shorter than the one below, we have that:

Bottom stair = 3 feet

Second stair = 2.666 feet

Third stair = 2.333 feet

Top stair = 2 feet

The staircase have 4 stairs:

3 feet, 2.666 feet, 2.333 feet and 2 feet

Now, to know the total length of wooden boards, we just need to sum the length of each stair:

Total = 3 + 2.666 + 2.333 + 2 = 10 feet

As 10 is a whole number, it can't be written as an improper fraction.