Mean or Average is all of the sums divided by how many of the choices are there, so all of 10,126+9,99+12,398+12,007+4567=49097 and divided by all the choices you have which is 5 is 9819.4
9/xy + x^2/y = (9+x^3)/xy
Answer:
15 years old
Step-by-step explanation:
Let's say Amanda's age is a, Brantley's age is b, and Carlos's age is c.
"Amanda is 3 years older than Brantley" means that a = 3 + b
"Carlos is twice as old as Amanda" means that c = 2 * a = 2a
"The sum of their ages is 57" means a + b + c = 57
We know that a = 3 + b, which can be written as b = a - 3. Substitute a - 3 in for b and 2a in for c in the equation a + b + c = 57 so that we have one variable to solve for:
a + b + c = 57
a + (a - 3) + 2a = 57
4a - 3 = 57
4a = 60
a = 15
Amanda is 15 years old.
