Number Foundations practice questions — Honors Math

The second decimal is $6\ge 5$, so the first decimal rounds up: $4.9\to 5.0$ (the $9$ carries to give $5.0$).

$0.2={\displaystyle \frac{2}{10}}={\displaystyle \frac{1}{5}}$.

$49.2\approx 50$ and $5.1\approx 5$, so the estimate is $50\times 5=250$.

${\displaystyle \frac{3}{5}}=0.6$ and $58\mathrm{\%}=0.58$.

Since $0.6>0.58>0.55$, the largest is ${\displaystyle \frac{3}{5}}$.

$6=2\cdot 3$ and $8=2^3$.

Highest powers: $2^3$ and $3$.

$\text{LCM}=8\cdot 3=24$.

$3\times 4=12$, then $2+12=14$.

$(5+1{)}^2=6^2=36$, then $36÷4=9$.

$3+4=7$; $2\times 7=14$; $20-14=6$.

The third decimal digit is $8\ge 5$, so round the second decimal up: $3.728\approx 3.73$.

$51=3\cdot 17$, $57=3\cdot 19$, $63=7\cdot 9$.

$59$ has no factor up to $\sqrt{59}<8$, so $59$ is prime.