Multiplying decimals - class-VII

$7.854$

$0.05 \times 0.09 \times 5$

In option A,

$5.\overline { 07 } \quad \times 10=50.7070707=50.7\overline { 07 } $

The rule of thumb in multiplying decimal numbers is we'll count the decimals from the right-hand side and the total places in the decimal in the question will be in the answer.

$14.79\times 1000 = 14790$

$0.126\times100$

$4\times 162=648$. Sum of decimal places $= 6$.
So, $0.04\times 0.0162=0.000648=6.48\times { 10 }^{ -4 }$

It can be solved as $27\times 1.\overline {2} \times 5.526\overline {2} \times 0.\overline {6}$
$= 27\times \left (1 + \dfrac {2}{9}\right )\times \dfrac {6}{9} \times (5.526\overline {2})$
$= 27\times \dfrac {11}{9}\times \dfrac {2}{3}\times (5.526\overline {2})$
$= 22\times (5.526\overline {2})$
$= 22\times (5.5 + 0.026\overline {2})$
$= 121 + (22\times 0.026\overline {2})$
$= 121 + 0.\overline {57}$
$= 121.\overline {57}$

$\dfrac { 489.1375\times 0.0483\times 1.956 }{ 0.0873\times 92.581\times 99.749 } \approx \dfrac { 489\times 0.05\times 2 }{ 0.09\times 93\times 100 } $
$=\dfrac { 489 }{ 9\times 93\times 10 } $
$=\dfrac { 163 }{ 279 } \times \dfrac { 1 }{ 10 } $
$=\dfrac { 0.58 }{ 10 } $
$=0.058\approx 0.06$.

Step 1 : $197 x 4 = 788$

Step 1 : $5 \times  7 = 35$

Given, $4.3 \times  3.4$

Given, $0.5 \times  0.05$

$2 \times 0.86 = 1.72$

Multiplying 0.1 by 7.5 is equivalent to moving the decimal point one place to the left, resulting in 0.75.

Given, $70.01 \times  1.1$

Given, $1.07 \times  0.02$

Given, $10.05 \times  1.05$

Given, $101.01 \times 0.01$

Using distributive property, we have
$0.25\times 12 = 0.25 \times (3 + 3 + 6)$
$\Rightarrow 0.25\times 12 = 0.25 \times 3 + 0.25\times 3 + 0.25 \times 6$.

The value of $5.25\times 9.1\times 0.0\times 8.26$ is

Given expression 

It is given that each piece of cardboard is $0.3$ cm thick which means that one piece is $0.3$ cm thick.

Let $x$ be the missing number.

Let $x$ be the missing number.

We know that 100 paise is nothing but 1 Rupee.

Step 1 : $21001 x 5 = 105005$

Multiplying 1.5 by 0.3 equals 0.45. The statement is correct.

Given

$25.4\times24.6$

we can re-wright them as

$(25+0.4)\times (25-0.4)$

$\because \ we \ have \ an\ identity \ (a+b) (a-b)=a^2-b^2$

$a=25,\ b=0.4$

$= (25)^2-(0.4)^2$

$= 625- 0.16$

$=624.84$

$\therefore option\ A\ is\ correct.$

The product of $78.12$ and $1.5$ is

We know if we multiply $0$ by any number then result will be zero.