Question

Which numbers are greater than 7 × 10^−4? Choose all answers that are correct.

a. 8 × 10^−4
b. 9 × 10^−5
c. 4 × 10^−4
d. 3 × 10^−2
e. 7 × 10^−5

Answer 1

`10^(-n)=0.\underbrace{00...01}_(n)\\\\7*10^(-4)=7*0.0001=0.0007\\----------------\\a.\ 8*10^(-4)=8*0.0008=0.0008\leftarrow \huge\boxed{greater}\\\\b.\ 9*10^(-5)=9*0.00001=0.00009 \ \textless \ 0.0007\\\\c.\ 4*10^(-4)=4*0.0001=0.0004 \ \textless \ 0.0007\\\\d.\ 3*10^(-2)=3*0.01=0.03\leftarrow\huge\boxed{greater}\\\\e.\ 7*10^(-5)=7*0.00001=0.00007 \ \textless \ 0.0007`