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Example of number problem solving question 5
Question:
The sum of three consecutive multiples of 8 is 192, what are the three numbers?
Sulution:
the first of the three is x
the second of the three is (x + 8)
the third of the three is (x + 16)
given: the sum of three consecutive multiples of 8 is 192
so we get the equation:
x + (x + 8) + (x + 16) = 192
remove parentheses
x + x + 8 + x + 16 = 192
keep all variables in left side of the equation and move all numbers to the right side of the equation
3x = -8 -16 + 192
3x = 168
x = 56
x + 8 = 56 + 8 = 64
x + 16 = 72
so the first number is 56, the second number is 64 and the third number is 72.

Given the sum of three consecutive of 8 is 192. Then the first number is x, the second is (x + 8), the third number is (x + 16). Since the sum of three consecutive multiply of 8 is 192. Then x + (x + 8) + (x + 16) = 192. Keep all veriables in the left side of the equation and move the numbers into the right side of the equation. When move an item cross the equal sign, the item will change sign, which equivalent to add the same item on the both side of the equation. Combine similar (like) terms. Get the value of x, then test if the value of x satisfy the equation.