Answer:
D. 5
Step-by-step explanation:
Mean: (50+60)/2
110/2
55
Margin of error:
60 - 55
5
Step-by-step explanation:








Answer:
22 feet per second
Step-by-step explanation
15x5280=79,200
79,200/60=1320 feet per minute since 60 minutes per hour
1320/60=22 feet per second since 60 seconds per minute

That's 7.68% = 7.7% (rounded)
Note: C(5, 4) is the number of combinations of 5 things taken 4 at a time. You may have seen this written as

In general,
They give us the length of side of the square which is 3-7x.
To get an expression for the perimeter that is expressed as a product we have to multiply the expression 3-7x by four since every square has four sides. This will give us an expression of 4(3-7x). We than can use the distributive property to multiply everything inside the parenthesis by 4. This will give us an expression of 12-28x.