SAT Practice: Solving For a Variable in Terms of Another Practice 03

$A=P(1+\dfrac{r}{n})^{nt}$

Katherine used the formula above to do some calculations on her bank account. She starts off with an initial investment of $P$ , with an annual nominal interest rate of $r$ , which is compounded $n$ times per year over a period of $t$ years.

Which of the following gives $t$ in terms of $A$ , $P$ , $n$ , and $r$ ?

$t=\dfrac{\log{A} - \log{P}}{n \log{(1+\frac{r}{n})}}$

$t=n( \sqrt[n]{\dfrac{A}{P}} -1)$

$t= \dfrac{A}{P(1+rn)^n}$

$t=\dfrac{\log{A}}{\log{P(1+\frac{r}{n})}} ^n$

$F= \dfrac{9}{5} C+32$

The formula above is used to convert Fahrenheit to Celsius.

Which of the following gives $C$ in terms of $F$ ?

$C= \dfrac{9}{5} (F-32)$

$C= \dfrac{5F-160}{9}$

$C= \dfrac{5}{9} (F+32)$

$C= \dfrac{9F}{5} +32$

$P=2L+2W$

The formula above gives the perimeter of a rectangle, $P$ , in terms of length, $L$ , and width, $W$ .

Which of the following gives $L$ in terms of $P$ and $W$ ?

$L=\dfrac{2P}{W}$

$L=P-W$

$L=\dfrac{2W+P}{2}$

$L=\dfrac{P-2W}{2}$

$B=703 \dfrac{w}{h^2}$

Joan uses the formula above to calculate her body mass index (BMI). $B$ represents the BMI, $w$ is the person's weight, and $h$ represents the person's height.

Which of the following gives $w$ in terms of $B$ and $h$ ?

$w=\dfrac{Bh^2}{703}$