Answer
$5 \text{ ft. 6.35 in.}$
Work Step by Step
If at the age of $10$ Dana has reached $84.4 \%$ of her adult height and Dana's height now is $4$ ft. and $8$ in.
Convert her height at the age of $10$ in inches ($1$ ft $= 12$ in.):
$4\cdot 12+8=56$
Therefore we have:
$\text{Adult height} = \text{height}\dfrac{100\%}{84.4\%}=56 \text{ in.} \dfrac{100\%}{84.4\%}\approx 66.35 \text{ in.}$
Convert to feet:
$\text{Adult height} = \dfrac{66.35}{12}=5 \text{ ft. 6.35 in.}$
