Answer:
The number is 8.
Step-by-step explanation:
Rewrite the word problem as an equation.
The sum of (we will be adding.), half of a number (we can use x, this will be written as x/2.) and double the number (this will be written as 2x) is 20.
To find the number, solve the equation.
x/2 + 2x = 20
Multiply both sides by 2.
x + 4x = 40
Combine terms.
5x = 40
Divide both sides.
x = 8.
There is no other equations
Recycles itself in the environment
$315, i cant give a thorough explanation since i did it all in my head but basically amal gets 5 portions of the money and Salma gets 9, meaning she gets 4 more, so if 4 portions is $252 then it cant be any of the others since they are too low or way too high, $315 is the only reasonable one.
Answer:
Sn = -9(1-(-3)^n)/4
Step-by-step explanation:
Since r < 1, the sum of nth term of a geometric sequence is expressed as;
Sn = a(1-r^n)/1-r
a is the first term
n is the number f terms
r is the common ratio
An = -9(1-(-3)^n)/1-(-3)
Sn = -9(1-(-3)^n)/4
Hence the sum of the nth term of the series is Sn = -9(1-(-3)^n)/4