Question

Work out in a standard form. A) 2.1x 10^-5 ÷7 x 10^-2​

Answer 1

Answer: 3*10⁻⁴.

Step-by-step explanation:

$\displaystyle\\2,1*10^{-5}\div7*10^{-2}=\\\frac{2,1*10^{-5}}{7*10^{-2}}=\\ \frac{2,1}{7}*10^{-5-(-2)}=\\ 0,3*10^{-5+2}=\\0,3*10^{-3}=\\3*10^{-4}.$

Answer 2

$\huge\underline{\underline{\boxed{\mathbb {SOLUTION:}}}}$

Given:

▪ $\longrightarrow \sf{\dfrac{2.1 \times {10}^{5} }{7 \times {10}^{ - 2} } }$

First, rewrite the numerator in such a way that the coefficient 2.1 becomes 21:

$\small\longrightarrow \sf{\dfrac{21 \times {10}^{ - 6} }{7 \times {10}^{2} } }$

Divide the coefficient:

$\small\longrightarrow \sf{21 \div 7=3}$

Divide the base by subtracting the exponents of the base 10.

$\small\longrightarrow \sf{-6(-2) \Longrightarrow -6+2=-4}$

$\leadsto$ Hence, the quotient of the given expression has a coefficient of 3 and the exponent of the base 10 is -4.

$\small\longrightarrow \sf{3 \times 10^{-4}}$

$\huge\underline{\underline{\boxed{\mathbb {ANSWER:}}}}$

$\large \bm{The \: \: quotient \: \: is \: \: 3 \times {10}^{ - 4} .}$