Question

Medal reward
Which of the following is the best estimate of 5 and three-eighths minus 1 and nine-tenths?

4 and one-half

2 and one-half

3 and one-half

4

Answer 1

\[5\frac{3}{8} -1\frac{9}{10}=\frac{43}{8} -\frac{19}{10} =\frac{43\times10}{8\times10} -\frac{19\times8}{10\times8}\]
\[=\frac{430}{80} -\frac{152}{80}=\frac{430-152}{80} =\frac{278}{80}=3.475\]

Answer 2

Ans 3 and one-half

Answer 3

\[3.475\approx 3.5 = 3 \frac{1}{2}\]