Company Alpha can produce 500 desks in 3 days while Company Beta can produce 700 desks in 4 days. If the two companies join forces, how many days would it take them to produce 3000 desks?
about 7 days
about 9 days
about 11 days
about 13 days

Pump 1 can empty a pool in 5 hours while Pump 2 can empty the same pool in 9 hours. If the two pumps were to work together, how long would it take them to empty the pool?

about 3 hours
about 3 hours and 15 minutes
about 3 hours and 30 minutes
about 3 hours and 45 minutes

Respuesta :

both answers are b im positive of it
 
For the first one
500 divided by 3 is about 167 and 700 divided by 4 is 175.
167+175 = 342
3000÷342 is 8.7 which rounds to 9.