Question

Describe and correct the error in converting 80 ounces to pounds.

$80 \text{ounces} = 80 \text{ounces} · \frac{\text{16} \text{ounces} }{\text{1} \text{pound}} \text{=} \text{1280} \text{pounds}$

Short answer

$80 \text{ounces} = \text{5} \text{pounds}$

Step-by-step solution

Step-1 – Multiplication factor of ounces to pound 

We know that 1 pound = 16 ounces

To convert ounces to pounds, the multiplication factor $\frac{16 \text{ounces}}{1 \text{pound}}$is incorrect.

The correct multiplication factor is $\frac{\text{1} \text{pound}}{\text{16} \text{ounces} }$

Step-2 – Example for conversion of 128 ounces

We know that 1 pound = 16 ounces.

To convert ounce into pound the multiplication factor is $\frac{\text{1} \text{pound}}{\text{16} \text{ounces} }$

$128 \text{ounce} = 128 \text{ounces} · \frac{\text{1} \text{pound}}{\text{16} \text{ounces} } \text{=} \text{8} \text{pounds}$

Step-3 – Convert 80 ounces into pounds

We know that 1 pound = 16 ounces.

To convert ounce into pound the multiplication factor is $\frac{\text{1} \text{pound}}{\text{16} \text{ounces} }$

$80 \text{ounces} = 80 \text{ounces} · \frac{\text{1} \text{pound}}{\text{16} \text{ounces} } \text{=} \text{5} \text{pounds}$

$80 \text{ounces} = \text{5} \text{pounds}$

To convert ounces to pounds, the multiplication factor $\frac{16\text{pounds}}{1\text{pound}}$is incorrect.

The correct multiplication factor is $\frac{1\text{pounds}}{\text{16pound}}$