Question

in many cases, a baby’s weight at birth is equal to one half his or her weight at age one.Explain how to estimate the weight of a baby at birth if this baby weights 18 pounds at age one.

Answer 1

The weight at birth is half the weight at age 1, so if the baby weighs 18 lb at age 1, it weighs half of that, or 9 lb, at birth. Divide the weight at age 1 by 2 to find the weight at birth.

Answer 2

If x is the weight at birth and y is the weight at age one, then this could be represented by the following equation:
y = 2x
If y = 18, we can solve this one-step equation:
18 = 2x
By dividing each side of the equation by 2.
9 = x
The baby was 9 pounds at birth.
Hope this helps!