13 9/20 + 2 3/5 + 12 1/8

⚠ 13 9/20 is read as the mixed number 13 + 9/20■2 3/5 is read as the mixed number 2 + 3/5■12 1/8 is read as the mixed number 12 + 1/8

Let's evaluate:

13

+ \frac{9}{20}

+ 2

+ \frac{3}{5}

+ 12

+ \frac{1}{8}

ⓘ Start from

13

and move forward

2

on the number line:

13 + 2

15

■Add fractions by using a common denominator and then adding their numerators:

\frac{9}{20} + \frac{3}{5}

\frac{9 + 4 \times 3}{20}

15

+ \frac{9 + 4 \times 3}{20}

+ 12

+ \frac{1}{8}

ⓘ Multiplications are done before additions and subtractions:

4 \times 3

12

■Start from

15

and move forward

12

on the number line:

15 + 12

27

27 + \frac{9 + 12}{20} + \frac{1}{8}

ⓘ Calculate the numerator and denominator before dividing:

9 + 12

21

27 + \frac{21}{20} + \frac{1}{8}

ⓘ Add fractions by using a common denominator and then adding their numerators. We choose

40

, the least common multiple of

20

and

8

. Multiplying the numerator and the denominator by the same number does not change the fraction:

\frac{21}{20} + \frac{1}{8}

\frac{21 \times 2}{20 \times 2} + \frac{1 \times 5}{8 \times 5}

\frac{21 \times 2 + 1 \times 5}{20 \times 2}

\frac{21 \times 2 + 5}{20 \times 2}

27 + \frac{21 \times 2 + 5}{20 \times 2}

ⓘ Multiplications are done before additions and subtractions:

21 \times 2

(20 + 1) \times 2

20 \times 2 + 2

40 + 2

42

ⅰ

20 \times 2

40

27 + \frac{42 + 5}{40}

ⓘ Calculate the numerator and denominator before dividing:

42 + 5

47

27 + \frac{47}{40}

▶Result:

28

\frac{7}{40}

ⓘ Since the fraction

\frac{47}{40}

exceeds 1, take

1

out of it and add it to the whole part:

27 + \frac{47}{40}

27 + \frac{40 + 7}{40}

27 + \frac{40}{40} + \frac{7}{40}

27 + 1 + \frac{7}{40}

28 + \frac{7}{40}

The numeric value of:

28 + \frac{7}{40}

equals:

28 + 0.175

▷

28.175

100% free