Okay, so the rate is 1 job / hours, so:
1/3 + 1/7 (This covers both their work rates) = 1/n (n represents the time it take for them to work together)
Get the LCD:
7/21+ 3/21 = 1/n
10/21 = 1/n
Cross multiply:
10n = 21
n = 2.1
It will take them 2.1 hours, or 2 hours and 6 minutes
Answer:
as long as a pizza crust
Step-by-step explanation:
yuh yuh yuh yuh yuh yuh
I think your answer might be 19.5
2 pages per hour.
the fractions can be turned to decimals easily, 4/5 is 0.8 and 2/5 is 0.4 . divide those decimals together and you get 2.
