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Example1

Title: Fractions

Grade Lesson s1-p2

Explanation: The best way to understand PSAT-4 is by looking at some examples. Take turns and read each example for easy understanding.

Examples

Topics → Definition Example1 Example2

Add \$3 8/10\$ + \$4 15/20\$.

Step: 1

First, convert the given mixed fractions into improper fractions.
\$3 8/10\$ = \$38/10\$.

\$4 15/20\$ = \$95/20\$.
To find a common denominator. The least common multiple (LCM) of 10 and 20 is 20.

$1a$

Explanation:

In this step, convert the given mixed fractions to improper fractions. For the mixed fraction \$3 8/10\$, the improper fraction is \$38/10\$. For \$4 15/20\$, the improper fraction is \$95/20\$. Since the denominators are different, find the least common multiple (LCM) of the denominators. In this case, 20 is a common multiple of 10 and 20.

Step: 2

In this step, to make the denominators equal, we must multiply \$2/2\$ by \$38/10\$ and \$1/1\$ by \$95/20\$.

This results in \$76/20\$ and \$95/20\$, respectively. Finally, add the numerators. ⇒ \$76/20\$ + \$95/20\$
⇒ \$171/20\$

$2a$

Explanation:

In this step, to find the LCM as the new denominator, multiply both the numerator and denominator of each fraction by a number, \$76/20\$ and \$95/20\$. To find the sum of the fractions, add their numerators and keep the denominator as 20. The result is \$171/20\$.