Oldest = 2x
Middle = x + 5
Youngest = x
2x + x + 5 + x = 57
combine like terms
4x + 5 = 57
subtract 5 from both sides
4x = 52
divide both sides by 4 to isolate x
x = 13
Oldest = 2x = 2(13) = 26
Middle = x + 5 = 13 + 5 = 18
Youngest = x = 13
Answer to the question is: I
Yes, a statistical question is a wuestion that can have multiple answers to figure out the main answer like first you have to figure out how many baseball cards there are then how many in all
In mathematical notation, ∑ means summation. So wherever you see the symbol, you have to sum over all elements in the set. Let's solve the question.
a. ∑m means, to sum all elements in the set m: ∑m = 12 + 15 + 20 + 30 = 77
b. ∑
means to sum all elements in the set f as the square of the elements f = 
c. ∑mf means to sum all elements as the product of the elements of m and f = (12×5) + (15×9) + (20
10) + (30×16) = 875
d. ∑
means to sum all elements as the product of the square of m and f = 
Answer:
21 and 30
Step-by-step explanation:
x + y = 51
x - y = 9
add the two equations and y's will cancel out
2x = 42 divide by 2
x = 21 so put 21 in for x in the top equation and solve
21 + y = 51
y = 30
