Respuesta :
Answer:
The answer to your question is a) C + J + S = 80
b) C = J + 5
c) S = 45 hours
Step-by-step explanation:
a) To represent the number of hours that they work together, just add the variables and equal them to 80.
Carlito + Juan + Sara = 80
C + J + S = 80 Equation l
b) Juan worked 5 hours more than Carlito
Juan = Carlito + 5
J = C + 5 Equation ll
c) Hours worked by Sara
S = 3J Equation lll
C = J - 5
Substitute equation ll and lll in equation l to find J
J - 5 + J + 3J = 80
5J = 80 - 5
5J = 75
J = 75/5
J = 15
-Find S
S = 3(15)
S = 45 hours
Answer:
Step-by-step explanation:
Let C represent the number of hours that Carlito worked.
Let J represent the number of hours that Juan worked.
Let S represent the number of hours that Sara worked.
1) The equation that would represent the fact that altogether they worked 80 hours is
C + J + S = 80
2) The equation that would represent the fact that Juan worked 5 more hours than Carlito is
J = C + 5
3) Sara worked 3 times as many hours as Juan. It means that
S = 3J
Substituting J = C + 5 into S = 3J, it becomes
S = 3(C + 5)
S = 3C + 15
Substituting S = 3C + 15 and
J = C + 5 into C + J + S = 80, it becomes
C + C + 5 + 3C + 15 = 80
C + C + 3C + 5 + 15 = 80
5C + 20 = 80
5C = 80 - 20
5C = 60
C = 60/5
C = 12
S = 3C + 15 = 3 × 12 + 15
S = 51 hours
Sara worked for 51 hours