Answer:
Jane is 12 and Harvey is 36
Step-by-step explanation:
100miles in 2hrs
650miles in x hrs
If you think of it 650/100 = 6.5
So the distance is 6.5 times
So the time is 6.5 times 2hrs
=13 hrs total
Answer:
C. y +3 = x +3
Step-by-step explanation:
We need to find in below option x has direct variation with y.
We solve for each;
A. 
From above equation we can state that 2 times y is equal to 7 less than 3 times of x.
Hence it doesn't represent direct variation.
B. 
Solving above expression we get;

From above equation we can state that y is equal to 10 more than x.
Hence it doesn't represent direct variation.
C. 
Solving above expression we get;

From above equation we can state that y is equal to x.
Hence it represent direct variation.
D. 
Solving above expression we get;

From above equation we can state that 4 times y is equal to 2 less than 4 times of x.
Hence it doesn't represent direct variation.
Hence the Answer which represent direct variation of x and y is,
C. 
Suppose the larger pump alone can empty the tank in L hours, and the smaller pump can finish the job in S hours, then each hour the large pump empties 1/L portion of the tank, and the small pump empties 1/S per hour
Working together for three hours, they empty the whole tank, which is 100% of it, so 3/L+3/S=100%=1
Larger pump can empty the tank in 4 hours less than the smaller one, so L=S-4
replace L: 3/(S-4)+3/S=1
Make the denominator the same to solve for:
3S/[S(S-4)] +3(S-4)/[S(S-4)]=1
(3S+3S-12)/[S(S-4)]=1
(3S+3S-12)=[S(S-4)]
S^2-10s+12=0
use the quadratic formula to solve for S
S is about 8.6
The answer is not whole hour.