How do you simplify $2.1 \div 4.41$ $2.1 div 4.41$ ?

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Answer 1 · 2016-08-08T11:12:34

$= \frac{10}{21}$ $=10/21$

$2.1 \div 4.41$ $2.1-:4.41$
$= \frac{210}{441}$ $=210/441$
$= \frac{210}{(21) (21)}$ $=210/((21)(21))$
$= \frac{10}{21}$ $=10/21$

Answer 2 · 2016-08-08T12:38:27

$\frac{2.1}{{2.1}^{2}} = \frac{2.1}{2.1 \times 2.1} = \frac{1}{2.1}$ $2.1/2.1^2 = 2.1/(2.1xx2.1) = 1/2.1$

It is very useful to know some of the squares and other powers by heart.

$21 \times 21 = 441$ $21 xx21 = 441$

In this case we could notice that the same numbers are used, just with decimals.

There are 2 decimal places in 4.41 and only one in 2.1

This leads us to realise that $2.1 \times 2.1 = 4.41$ $2.1 xx2.1 = 4.41$

And consequently: $\frac{2.1}{{2.1}^{2}} = \frac{2.1}{2.1 \times 2.1} = \frac{1}{2.1}$ $2.1/2.1^2 = 2.1/(2.1xx2.1) = 1/2.1$

How do you simplify 2.1÷4.412.1 div 4.41?