Question

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

Answer 1

Answer: 3*10⁻⁴.

Explanation:

`\displaystyle\\2,1*10^(-5)/7*10^(-2)=\\(2,1*10^(-5))/(7*10^(-2))=\\ (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{\frac{2.1 * {10}^(5) }{7 * {10}^( - 2) } }`

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

`\small\longrightarrow \sf{\frac{21 * {10}^( - 6) }{7 * {10}^(2) } }`

Divide the coefficient:

`\small\longrightarrow \sf{21 / 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 * 10^(-4)}`

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

`\large \bm{The \: \: quotient \: \: is \: \: 3 * {10}^( - 4) .}`