In order to determine the correct answer, it would be helpful to set up equations. We do as follows:
Let x = students
y = adults
x + y = 215
.50x + 2y = 250
SOlving simultaneously, we have:
x = 120 students
y = 95 adults
Hope this answers the question. Have a nice day.
50*8=400
400+175=575
it subtracted 575 on the last round
Work it exactly like the other one with Wilda and Karla.
Juan takes 15 hours to do a job ... he does 1/15 of it in an hour.
His father can do it in 6 hours ... he does 1/6 of it in an hour.
Juan works alone for 4.5 hours. In that time, he does 4.5/15 = 0.3
of the job. When his father joins him, there's only 0.7 of it to finish.
Working together, they do (1/15 + 1/6) = (2/30 + 5/30) = 7/30 of the job
each hour.
How many times do they have to do 7/30 of the job in order to finish
the 7/10 of it that remains ? That will be the number of hours they need.
(7/10) / (7/30) = 7/10 x 30/7 = <em>3 hours</em>.
Then they can knock off while it's still daylight, and go for a swim.
I’m pretty sure you add 78+55= 133
180-133=47
so 9x+2=47
subtract 2 from 47 and itself
so 9x=45
divide 9 and 45 by 9
so x=5