Question

Draw fraction rectangles on dot paper to solve the problems.

1) Subtract: 3/5 - 1/4

2) Add: 5/6 + 1/4

3) Manny and Frank ordered pizza. Manny ate 1/4 of the pizza and Frank ate 5/8 of the pizza. How much of the whole pizza was eaten?

Answer 1

Answer:

1) $\frac{7}{20}$

2) $1\frac{1}{12}$

3) $\frac{7}{8}$

Step-by-step explanation:

1) Given problem,

$\frac{3}{5}-\frac{1}{4}$

LCM(5,4) = 20,

$\frac{3}{5}=\frac{3\times 4}{5\times 4}=\frac{12}{20}$

$\frac{1}{4}=\frac{1\times 5}{4\times 5}=\frac{5}{20}$

$\implies \frac{3}{5}-\frac{1}{4}=\frac{12}{20}-\frac{5}{20}=\frac{7}{20}$

2) Given problem,

$\frac{5}{6}+\frac{1}{4}$

LCM(6, 4) = 12,

$\frac{5}{6}=\frac{5\times 2}{6\times 2}=\frac{10}{12}$

$\frac{1}{4}=\frac{1\times 3}{4\times 3}=\frac{3}{12}$

$\implies \frac{5}{6}+\frac{1}{4}=\frac{10}{12}+\frac{3}{12}=\frac{13}{12}=1\frac{1}{12}$

3) ∵ Pizza ate by Manny = $\frac{1}{4}$

Pizza ate by Frank = $\farc{5}{8}$

∴ Total pizza eaten = $\frac{1}{4}+\frac{5}{8}$

LCM(4, 8) = 8,

$\frac{1}{4}=\frac{2}{8}$

Thus, total pizza eaten =  $\frac{2}{8}+\frac{5}{8}=\frac{7}{8}$