they keep returning and saying show work again

Answer:
We conclude that:
[tex]20\times \:3\frac{1}{5}=64[/tex]
Step-by-step explanation:
Given the expression
[tex]20\:\times 3\frac{1}{5}[/tex]
convert mixed number to improper fraction: [tex]a\frac{b}{c}=\frac{a\times c+b}{c}[/tex]
i.e. [tex]3\frac{1}{5}=\frac{3\times 5+1}{5}=\frac{16}{5}[/tex]
so the expression becomes
[tex]20\:\times 3\frac{1}{5}\:=20\times \:\frac{16}{5}[/tex]
Factor the number: 20 = 5×4
[tex]=5\times \:4\times \frac{16}{5}[/tex]
Cross-cancel common factor: 5
[tex]=4\times \:16[/tex]
Multiply the numbers: 4×16 = 64
[tex]=64[/tex]
Therefore, we conclude that:
[tex]20\times \:3\frac{1}{5}=64[/tex]