Fractions reducing to lower terms (simplifying). Equivalent fractions
Let's learn by an example, let's simplify the fraction: 12/16
Numerator of the fraction. The number that is above the fraction bar, 12, is called the numerator of the fraction;
Denominator of the fraction. The number that is below the fraction bar, 16, is called the denominator of the fraction;
The value of the fraction. Fraction 12/16 shows us in how many equal parts the number above the fraction bar, 12, is being divided: into 16 equal parts. Thus, the value of the fraction is calculated as:
12 ÷ 16 = 0.75
We notice that the two numbers, the numerator and the denominator, are dividing themselves without any remainder by 2, so we divide them by the same number, 2:
12/16 = (12 ÷ 2)/(16 ÷ 2) = 6/8
The value of the fraction 6/8 is calculated as:
6 ÷ 8 = 0.75
We notice that the value of the fraction 6/8 is equal to that of the fraction 12/16, namely 0.75
Reduced (simplified) fraction, Equivalent fraction. The new fraction, 6/8, is equivalent to the original one, 12/16, that is, it represents the same value or proportion of the whole, and it was calculated out of the original fraction by reducing it (simplifying it): both the numerator and the denominator of the fraction were divided by the number 2.
Common factor (divisor). The number 2 that was used to divide the two numbers that make up the fraction is called a common factor or a divisor of the numerator and the denominator of the fraction.
The reduced fraction has now a numerator that is equal to 6 and a denominator that is equal to 8.
We also notice that the two new numbers, the new numerator and the new denominator, 6 and 8, are also dividing themselves without any remainder by 2 (2 is a common factor of 6 and 8), so we divide them again by 2:
6/8 = (6 ÷ 2)/(8 ÷ 2) = 3/4
The value of the fraction 3/4 is calculated as:
3 ÷ 4 = 0.75
The new fraction, 3/4, is a reduced fraction (a simplified fraction) and an equivalent of the fractions 12/16 and 6/8
Irreducible fraction. Fraction 3/4 is also called an irreducible fraction, in another words it could no longer be reduced or simplified, it is in its simplest form, the numbers 3 and 4, the numerator and the denominator of the fraction, are coprime numbers (prime to each other), not having any common factors other than 1.