Answer:
The speed on motorboat is 20 mph
Step-by-step explanation:
here, we want to find the speed on the motorboat
if he has a speed of x mph on the motor boat, his speed on the ski will be (x + 10) mph
The total hours is 4 hours
Mathematically; speed = distance/time
Time on ski is 27/x+ 10
Time on motor boat is 62/x
The addition of both is 4
Thus;
27/(x + 10) + 62/x = 4
27(x) + 62(x + 10) = 4(x)(x + 10)
27x + 62x + 620 = 4(x^2 + 10x)
89x + 620 = 4x^2 + 40x
4x^2 -49x-620 = 0
using the quadratic formula;
{-b ± √(b^2-4ac)}/2a
where a = 4, b = -49 and c = -620
= 49 ± √(-49)^2-4(4)(-620)/8
So we have
49+ 111/8 or 49-111/8
Speed cannot be negative
(49 + 111)/8
= 20 mph
Recall that for a home visit, the technician charges $50 regardless on the time spent in the repair.
So, to find out the rate, we should calculate the part that depends on the spent time, and the add 50. So for example, we know that the technician spents 1 hour. So, we multiply 1 times 25 and then add 50. So, 25*1 + 50 = 75, which is the rate for a 1-hour repair.
So, in general, if we know that the number of hours is x, we multiply x times 25 and then add 50. Then a table would like this:
x 25*x 25*x +50
1 25 75
2 50 100
3 75 125
4 100 150
Note that as the time increases by one hour, the fare increases by 25. This is an example of a direct variation, since as the independent variable increases (t
Answer: 1,285, 1,282, 1,278
Step-by-step explanation:
Answer:
63
Step-by-step explanation:
First, I wrote the fraction as 1 63/100. I believe this is simplest form so the numerator is 63.
