Answer:
They are both the same at 3/4 of an hour
Step-by-step explanation:
We have a system of equations here. The first one is for Friday:
3A + 5B = 6, which says that 3 people at the number of hours for plan A plus 5 people at the number of hours for plan B equals 6 hours total.
The second equation is for Saturday:
9A + 7B = 12, which says that 9 people at the number of hours for plan A plus 7 people at th number of hours for plan B equals 12 hours total.
We can solve this easily using the addition/elimination method. Begin by multipying the first equation through by a -3 to eliminate the A's. That gives you a new first equation of:
-9A - 15B = -18
9A + 7B = 12
You can see that the A's are eliminated, and adding what remains leaves us with
-8B = -6 so
B = 3/4 hour
Now we can sub that back in for B in either one of our original equations to solve for A. I changed the 3/4 to .75 for ease of multiplying:
9A + 7(.75) = 12 and
9A + 5.25 = 12 and
9A = 6.75 so
A = .75 which is also 3/4 of an hour