Recall d = rt, distance = rate * time.
now, he has a speed rate of 56 mph for a distance of 504
so, at that speed the whole driving time is 9 hours then. Ok, he drove 2 hours today, that means he drove 7 yesterday, 9 - 2.
how many miles is it for 7 hours at 56mph? d = rt ---> d = 56 * 7
that many miles he drove yesterday.
Answer:
4
Step-by-step explanation:
And let the missing number be x
We can solve using Algebra
11x - 10 = 34
11x = 34 + 10
11x = 44
x = 44/11
x = 4
For verification:
4(11) - 10 = 34
44 - 10 = 34
34 = 34
Hence, Proved
The number of cows is given by
So, after 
years, the number of cows will be
We want this number to be twice as much as the original:
First of all, we can cancel 14 from both sides:
Finally, on the right hand side, we can use the exponent rule
to get
To solve this equation, we must impose that the two exponents are the same:
And clearly this is true if and only if 
. So, it will take 5 years for the cow heard to double in number.
You can do the exact same steps to find the doubling time for the sheeps.
D + q = 40
.10d +.25q= $7.75
d +q = 40
d =40-q
.10(40-q) +.25q= $7.75
4 - .10q + .25q =7.75
4 +.15q =7.75
4-4 +.15q =7.75-4
.15q= 3.75
.15q/.15 = 3.75/.15
q = 25
d =40-25
d = 15
Check
.10(15) +.25(25)= $7.75
1.5+6.25=7.75
7.75=7.75
