Mr. Ailey gave his class 45 minutes to read. Davida reads 27 3/4 pages in that time. At what rate, in pages per hour, did Davida read? A 42
B 36
C 34
D 37

37 pages per hour

Step-by-step explanation:

Given that :

Time Given to read = 45 minutes ; 45 / 60 = 0.75

Number of pages readable ad by Davida within the given time frame = 27 3/4 pages

David's reading rate in pages per hour :

Number of pages read / time taken (hrs)

[27 3/4] ÷ (45/60)

[111 / 4] ÷ (45/60)

(111 / 4 ) * (60/45)

(111 * 60) / (4 * 45)

6660 / 180

= 37 pages per hour

a negative exponent is translated as follows:

so, we have

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.