To solve the first problem, we need to find the time difference between Jake and Lily. To do this, we will convert both their times to minutes:
Jake's time = 1 hour + 33 minutes + 32 seconds = 60 minutes + 33 minutes + 32/60 minutes = 93.53 minutes.
Lily's time = 2 hours + 52 minutes = 120 minutes + 52 minutes = 172 minutes.
Now, we can subtract Lily's time from Jake's time to find the difference:
93.53 minutes - 172 minutes = -78.47 minutes.
Since we want to find the difference in minutes, we round -78.47 to the nearest minute, which is -78 minutes. However, a negative value does not make sense in this context, so we take the absolute value of -78 to get 78 minutes. Therefore, Jake was 78 minutes faster than Lily to the nearest minute.
For the second problem, we are given that it took 30 years to build the Great Pyramid at Giza with 2,300,000 blocks. To find the average number of blocks placed per hour, we need to divide the total number of blocks by the total number of hours:
Total number of hours = 30 years * 365 days/year * 24 hours/day = 262,800 hours.
Average number of blocks per hour = 2,300,000 blocks / 262,800 hours ≈ 8.75 blocks per hour.
So, the correct answer is approximately 8.75 blocks placed on the pyramid per hour.
Now, let's solve the third problem. We are given that in order to qualify for the Boston Marathon, a runner must have a time of 3 hours and 20 minutes in another marathon, which is equivalent to 200 minutes.
The marathon distance is 26.2 miles. To find the runner's pace in minutes per mile, we divide the total time (200 minutes) by the distance (26.2 miles):
Pace = Total time / Distance = 200 minutes / 26.2 miles ≈ 7.63 minutes per mile.
To the nearest 10th of a minute, the runner's pace in order to complete 26.2 miles in 3 hours and 20 minutes is approximately 7.6 minutes per mile.
So, your answer of 7.6 is correct.