Question

One month ruby worked 8 hours more than Issac,and Shetland worked 4 times as many hours as ruby. Together they worked 136 hours. Find the number of hours each person worked.

Answer 1

r=number of hours ruby worked
i=number of hours issac worked
s=number of hours shetland worked


ruby worked 8 more than issac
r=8+i


shetland worked 4 times as many as ruby
s=4r

total they worked 136
r+i+s=136

so

we gots
r=8+i
s=4r

for r=8+i
solve for i
minus 8 both sides
r-8=i

so

r+i+s=136
subsitute r-8 for i and 4r for s
r+r-8+4r=136
6r-8=136
add 8 to both sides
6r=144
divide both sides by 6
r=24

sub back


r-8=i
24-8=i
16=i


s=4r
s=4(24)
s=96


ruby worked 24 hours
issac worked 16 hours
shetland worked 96 hours