Question

determine if the answer given is true or false.
1
$(7.4 \times 10^{-3}) - (4.9 \times 10^{-3}) = 2.5 \times 10^{-3}$
t f
2
$(6.5 \times 10^{-6}) - (9.3 \times 10^{-7}) = 5.57 \times 10^{-7}$
t f
3
$(12.62 \times 10^{3}) - (12.4 \times 10^{3}) = 2.2 \times 10^{3}$
t f
4
$(8.23 \times 10^{2}) - (15.6 \times 10^{-1}) = 8.2144 \times 10^{2}$
t f

Explanation:

Problem 1

Step1: Factor out \(10^{-3}\)

\((7.4\times10^{-3})-(4.9\times10^{-3})=(7.4 - 4.9)\times10^{-3}\)

Step2: Subtract the coefficients

\(7.4-4.9 = 2.5\), so \((7.4 - 4.9)\times10^{-3}=2.5\times10^{-3}\)

Step1: Rewrite \(6.5\times10^{-6}\) as \(65\times10^{-7}\)

\((6.5\times10^{-6})-(9.3\times10^{-7})=(65\times10^{-7})-(9.3\times10^{-7})\)

Step2: Subtract the coefficients

\(65 - 9.3=55.7\), so \((65 - 9.3)\times10^{-7}=55.7\times10^{-7}=5.57\times10^{-6}
eq5.57\times10^{-7}\)

Step1: Factor out \(10^{3}\)

\((12.62\times10^{3})-(12.4\times10^{3})=(12.62 - 12.4)\times10^{3}\)

Step2: Subtract the coefficients

\(12.62-12.4 = 0.22\), so \((12.62 - 12.4)\times10^{3}=0.22\times10^{3}=2.2\times10^{2}
eq2.2\times10^{3}\)

Answer:

T

Problem 2