Answer:
-12.5%
Step-by-step explanation:
The percentage change in your time can be computed using ...
pct change = ((new value)/(old value) -1) × 100%
= (28/32 -1) × 100%
= (0.875 -1) × 100% = -12.5%
The time to finish level 2 decreased by 12.5%.
Note that the formula for the circumference of a circle is πd, while the formula for the area of a circle is πr².
π≈3.14
A. C=πd
Simply plug in the numbers into the formula.
Diameter=Radius*2
17*2=34
C=34(π)
B. (π)(5²)
Plug in the numbers into the formula. Remember that half of the diameter is the radius.
C. (π)(4.5)
There are two possible formulas that could be used to calculate the circumference of a circle: πd and 2πr.
The expression above is simply multiplying the circle's radius times pi. Therefore, it is not a method that could be used to find the circumference of a circle.
D. (π)(6.5²)
Remember that the formula for calculating the area of a circle is πr².
Half of the diameter is 6.5 (13.5/2=6.5). 6.5 cm. is the radius. Now just plug the numbers into the formula.
(π)(6.5²)
Therefore, the last answer choice is the correct answer.
Answer:
and?
Step-by-step explanation:
???
The answer would be -37.5
The answer is 28.27 cm because the formula for area of a circle is A=
*r^2. Hope this helped!
