Answer:
21 mph
Step-by-step explanation:
The relationship between time, speed, and distance is ...
time = distance/speed
The speed downstream is b+7 if the boat's speed is b. The speed upstream is b-7, and the times in each direction are equal. This means ...
20/(b+7) = 10/(b-7) . . . . . . time in each direction are the same
20(b-7) = 10(b+7) . . . . . . . cross multiply
(20-10)b = 7(10+20) . . . . . add 7(20)-10b
b = 7(20 +10)/(20 -10) = 21 . . . . mph
The speed of the boat in still water is 21 mph.
That would be the ones place, because 7 would be the tens place, 6 would be the hundreds place, and 5 would be the thousands place.
Hope this helped >.<
The two number are 39 and 13
<em><u>Solution:</u></em>
Let the two numbers be "a" and "b"
Let the larger number be "a" and the smaller number be "b"
<em><u>Given that, sum of two numbers is 52</u></em>
a + b = 52 ---------- eqn 1
<em><u>One number is 3 times as large as the other number</u></em>
Larger number = 3 times smaller number
a = 3b -------- eqn 2
<em><u>Let us solve eqn 1and eqn 2</u></em>
<em><u>Substitute eqn 2 in eqn 1</u></em>
3b + b = 52
4b = 52
b = 13
<em><u>Substitute b = 13 in eqn 2</u></em>
a = 3(13)
a = 39
Thus the two number are 39 and 13
Function a has a rate of change of 2 and function b has a rate of change of .75. So function a has a greater rate of change.