<h2>
Answer:</h2>
The length of the three yards when they are placed end to end is:
14.125 yards.
( Since, Length of first strip = 3.5 yards.
Length of Second strip = 4.375 yards.
Length of Third strip = 6.25 yards. )
<h2>
Step-by-step explanation:</h2>
It is given that:
3 strips of 2 yard wide outdoor carpet are used to cover a sidewalk.
- Second is 25 percent longer than the first.
i.e. the length of the second strip is: 3.5+25% of 3.5
i.e.
Length of second strip= 3.5+0.25×3.5
i.e.
Length of second strip= 4.375 yards
- Also, the third is 6 1/4 yards long.
i.e. The length of third strip is:

Hence, the total length of three carpets is:
3.5+4.375+6.25= 14.125 yards.