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.
All of the centra angles in a regular polygon must add up to 360 degrees. Also, because you're told that it is a regular polygon, the "regular" indicates that all of the central angles will be the same. Divide 360 degrees by 18 degrees to get the number of central angles, which is the same as the number of sides. 360/18 = 20. Therefore, the polygon has 20 sides. Hope that helps!
Answer:
Step-by-step explanation:
X=−13
Distribute
Subtract
simplify
divide both sides
then simplify again to arrive at your answer.
F(x + 1) = (5/2)*f(x)
f(x + 1) = 2.5*f(x), f(1) = 3.2
f(2) = 2.5f(1) = 2.5*3.2 = 8
<span>f(3) = 2.5f(2) = 2.5*8 = 20
</span>
f(4) = 2.5f(3) = 2.5*20 = 50
<span>f(5) = 2.5f(4) = 2.5*50 = 125</span>