Let m and r represent the maximum speeds of Malcolm and Ravi in km/h, respectively.
... (m + r)/2 = 260 . . . . . the average of their speeds was 260 kph
... 2m = r + 80 . . . . . . . . double Malcolm's speed is 80 kph more than Ravi's
The second equation can be solved for r and that expression substituted into the first equation.
... 2m - 80 = r . . . . . . . . . . . an expression for r from the second equation
... (m + 2m - 80)/2 = 260 . . . the result of substituting that into the first
... 3m - 80 = 520 . . . . . . . . multiply by 2
... m = 200 . . . . . . . . . . . . . add 80 and divide by 3
... 2·200 - 80 = r = 320 . . .substitute the value of m into the expression for r
Malcolm's maximum speed was 200 km/h.
Ravi's maximum speed was 320 km/h.
Tim spends 1/3 each weekday sleeping and 7/24 in school. We can write 1/3 as 8/24 so we have a common denominator. Now we can see that Tim sleeps for 1/24 time of a weekday more then he spends in school.
I hope that's what you meant.
The answer is either c or d. I would go with answer c though. sorry if it is wrong
9514 1404 393
Answer:
A(x) = 20000(0.88)^x
Step-by-step explanation:
The general form of these exponential equations is ...
A(x) = a·b^x
where 'a' is the initial value, and b is the annual growth factor. x is the elapsed time in years.
The growth factor is ...
growth factor = 1 + growth rate
Here, the growth rate per year is -12%, so the growth factor is ...
b = 1 -12% = 88% = 0.88
Of course, the initial value is a=20,000, so the equation is ...
A(x) = 20000(0.88)^x
