Let
x--------> <span>the speed of the boat in mph
we know that
</span>going upstream the speed is x-7
<span>going downstream the speed is x+7
</span>
let the distance be d
<span>time to go upstream = d/(x-7) </span>
<span>time to go downstream = d/(x+7)
</span>
time going upstream is 3 times going downstream
so
<span>3d/(x+7) = d/(x-7) </span>
<span>divide by d </span>
<span>3/(x+7) = 1/(x-7) </span>
<span>3x-21 = x+7 </span>
<span>2x = 28 </span>
<span>x = 14
</span>
the answer is
<span>the speed of the boat in still water is 14 mph</span>
Answer:
1.23 repeating
Step-by-step explanation:
divide 37 and 30
Answer:
Step-by-step explanation:
this goes with BODMAS .so it means bracket of divison,multiplication ,addition and subtraction
this means that you would have to solve the one in the bracket first before you'll continue with the rest,that is the subtraction.
I think it is B
Hope this help you?????
If the standard deviation of an exam is 5, the z-score us 1.95 and the mean is 80, the actual test score is; 89.75
<h3>How to solve z-score problems?</h3>
We are given;
Standard deviation; s = 5
z-score = 1.95
Mean = 80
Formula for z-score is;
z = (x' - μ)/σ
Thus;
1.95 = (x' - 80)/5
1.95 * 5 = (x' - 80)
9.75 = x' - 80
x' = 80 + 9.75
x' = 89.75
Read more about Z-score Problems at; brainly.com/question/25638875
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