# Question 8da01

Jun 15, 2017

See the process down below

#### Explanation:

First, let's start by converting $65 \text{cm}$ to $\text{in}$

$1 \text{ in"=2.54"cm}$

Set up a conversion factor:

$65 \cancel{\text{cm"*(1" in")/(2.54cancel"cm")= 25.59 " in}}$

Subtract this from the $57 \text{ in}$

$57 \text{in"-25.59"in"=31.41" in}$

Rounding this to the nearest $\text{inch}$ we get $31 \text{ in}$

P.S. I will also taking Physics in the fall and been planning to prepare now for it now too. Would happen to have any good resources you can pass by?

Jun 15, 2017

The answer is indeed $31$ $\text{in.}$

#### Explanation:

What we can do is calculate the number of inches cut off from the $57$-inch board. We know that the part cut off was $65$ $\text{cm}$ long, so this value in inches is

65cancel("cm")((1"in")/(2.54cancel("cm"))) = color(red)(26 color(red)("in" ($2$ significant figures)

The amount of board remaining is thus

$57$ "in" - color(red)(26 color(red)("in") = color(blue)(31 color(blue)("in"#

The only error you made in your calculation is the first conversion, from $\text{in}$ to $\text{cm}$. The value should be $144.78$ $\text{cm}$, not $54.46$ $\text{cm}$.