QUESTION:
Divide 50 by 1/2 and add 15, what is the result?
The correct ANSWER is ⇒ not 40 of course! It is 115
Let’s see how:
Dividing a number in half means multiplying it by 2. Fractions come into play here, and so when dividing a number in half, the divisors change as the numerator and denominator, so they become the same thing.
Illustration credit belongs to WikiHow.
Steps of Division by Fractions
∗ Leave the first fraction in the equation alone.
∗ Convert the slash to the multiplication sign.
∗ Reverse the numerator and denominator of the second fraction
∗ Multiply the numerators of the two fractions (top numbers) together. This result will be the numerator (upper part) of the answer.
∗ Multiply the denominators of two fractions (bottom numbers) together. This result will be the denominator of the answer.
∗ Simplify the fraction to the lowest value.
The second point of view:
The problem asks you: “How many halves are in 50?” The answer is 100 because a unit (1) consists of two halves and there are 50 units in total: 2 halves/1 unit * 50 units = 100 halves. Then you add 15 and get the result.