common difference, d = -3
f1 = -13
An arithmetic sequence f(n) = f1 + d(n - 1)
so f(n) = -13 - 3(n - 1)
f(46) = -13 - 3(46-1) = -13 -3(45) = -13 - 135 = -148
Answer:
f(46) = - 148
The number was 160 because 5/4•128=160. 5/4 represents inverting 80% and multiplying it by the number to determine how the result became 128. For checking over all you have to do is do 4/5 or 80%•160 which shall give you 128.
Answer: 30 feet per second
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x = diameter, y = speed of water
y varies inversely with respect to x, so, y = k/x for some constant k
If x = 0.6 and y = 5 pair up, then y = k/x turns into 5 = k/0.6 which solves to k = 3 when you multiply both sides by 0.6
So the equation y = k/x turns into y = 3/x
Now plug in the diameter x = 0.1 to find the speed to be...
y = 3/x
y = 3/0.1
y = 30 feet per second