Answer:
36
Step-by-step explanation:
9+9=18+18=36
Answer: 2102
Step-by-step explanation:
First we will calculate rate of work of rosa and amy.
work done by rosa in time t=t*1/7
Work done by Amy and rosa=t(1/7+1/4.2)
t/7+t/a=t/4.2
t=10.5 hr
Always keep remember those formula or logic belowWork rate × Time to finish the job = 1 job done
Work rate = (1 job done) / (Time to finish the job)
Time of doing the job = (1 job done) / (Work rate)
8a - 4 = 25 + 6 (a - 8)
(distribute the 6)
8a - 4 = 25 + 6a - 48
(combine like terms 25 - 48)
8a - 4 = 6a - 23
( subtract 6a from both sides)
2a - 4 = -23
(add 4 to both sides)
2a = -19
(divide both sides by 2)
a = - 9.5
////CHECK/////
8 (-9.5) - 4 = 25 + 6 ( -9.5 -8)
(plug each side into a calculator)
-80 = -80
FINAL ANSWER:
a = -9.5