Let his total money be x.
He spent (3/7)*x of his money.
He gave 1/4(x-3/7x) to his sister.
which is : (1/4)*(4/7)*x = (1/7)*x
Now,
How much money he have in the beginning =
(3/7)*x+(1/7)*x+120=x
(4/7)*x+120=x
120=x-(4/7)*x
120=(3/7)*x
x=120*7/3 [cross multiplication]
x=280.
So, Alex had $280 in the beginning.
Answer:
the answer to this question is 7.36....its equation is 16/100*46
Since 9 is a factor of an unknown number, that means that that number has to be a multiple of 9. If 9 is the factor of something then that something HAS to be a multiple of 9.
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