Answer: First half was 24 minutes
Step-by-step explanation:
Let the time taken to finish the second half be y.
Since the student used 2/3 of the second half time to finish the first half, first half = 2/3 × y = 2y/3
The entire exam is an hour which equals 60 minutes
First half + Second half = 60minutes
Note that first half is denoted as 2y/3 and second half is denoted by y.
2y/3 + y = 60
5y/3 = 60
Cross multiply
5y = 60 × 3
5y = 180
y = 180/5
y = 36
Second half took 36 minutes
Since first half is 2y/3, it will be:
(2×36) / 3
= 72/3
= 24minutes
First half took 24 minutes.
Circumference is diameter times pi, diameter is radius times 2. The answer should be 57 inches.
D has the commutative property because it just flip flopped the numbers.
