Answer:
ok
Step-by-step explanation:
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:
b = 6.928
Step-by-step explanation:
Looks like a job for the Pythagorean Theorem.
a^2 + b^2 = c^2
4^2 + b^2 = 8^2
16 + b^2 = 64
b^2 = 48
b = 6.928
Hope it helps!!