Tag: division trick

Questions Related to division trick

Multiple choice maths multiply and divide division trick division division of numbers

How many rational numbers exist between any two distinct rational numbers?

  1. 2

  2. 3

  3. 11

  4. Infinite number of rational numbers

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Infinite number of rational numbers exist between any two distinct rational numbers. We know that a rational number is a number which can be written in the form of $\frac { p }{ q } $ where p and q are integers and q $\neq $0.

Multiple choice maths multiply and divide division trick division division of numbers

If $n=2^3\times 3^4\times 7\times15^6$, then find the number of consecutive zeros in natural number n

  1. 6

  2. 3

  3. 2

  4. 1

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Consecutive zeros are formed by factors of 10 (2 * 5). n = 2^3 * 3^4 * 7 * (3*5)^6 = 2^3 * 3^10 * 7 * 5^6. The number of pairs of (2, 5) is min(3, 6) = 3.

Multiple choice maths multiply and divide division trick division division of numbers

State whether the statement is true or false.
$ \displaystyle \frac{4}{-9}   $ and $ \displaystyle \frac{-16}{36}   $ represent the same rational number?

  1. True

  2. False

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Yes beacause
$ \displaystyle \frac{4}{-9}   $=$ \displaystyle \frac{4\times (-4)}{9\times(-4)}   $= $ \displaystyle \frac{-16}{36}   $ 


or $ \displaystyle \frac{-16}{36}   $= $ \displaystyle \frac{-16\div -4}{36\div -4}   $ =$ \displaystyle \frac{4}{-9}   $

Multiple choice maths multiply and divide division trick division division of numbers

Solve it 
$\dfrac {\left( {{{\left( {245 + 232} \right)}^2} - {{\left( {245 - 232} \right)}^2}} \right)}{\left( {245 + 232} \right)}$

  1. $4$
  2. $2$
  3. $232$
  4. none of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
$=\dfrac{{\left(245+232\right)}^{2}-{\left(245-232\right)}^{2}}{\left(245+232\right)}$
$=\dfrac{\left(245+232-245+232\right)\left(245+232+245-232\right)}{\left(245+232\right)}$
$=\dfrac{2\left(232\right)2\left(245\right)}{\left(245+232\right)}$
$=\dfrac{2,27,360‬}{477}=476.65$
Multiple choice maths multiply and divide division trick division division of numbers

Let $Q = \dfrac{x}{y}$ where $x$ and $y$ are real numbers. If both $x$ and $y$ are increased equally then

  1. $Q$ will increase
  2. $Q$ will decrease
  3. $Q$ will remain the same
  4. none of the above

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If x/y = 1, adding 1 to both gives 2/2 = 1 (no change). If x/y < 1, adding a constant increases the ratio. If x/y > 1, adding a constant decreases the ratio. No single outcome is universal.

Multiple choice maths multiply and divide division trick division division of numbers

The value of $0.\bar { 1 } +0.0\bar { 1 } +0.00\bar { 1 } $ is equal to 

  1. $\dfrac{407}{3300}$
  2. $\dfrac { 37 }{ 3000 } $
  3. $\dfrac { 4 }{ 3300 } $
  4. $\dfrac { 1343 }{ 10989 } $
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
$0.\bar{1}+0.0\bar{1}+0.00\bar{1}$

Let $x=0.11111...+0.01111...+0.00111....$

$\Rightarrow x=0.12333...$

$\therefore x=0.123333...$

$\Rightarrow 100x=12.333...$

$\Rightarrow 100x-x=12.333333...-0.123333...$

$\Rightarrow 99x=12.210000....$

$\Rightarrow 99x=12.21$

$\Rightarrow x=\dfrac{12.21}{99}$

$\Rightarrow x=\dfrac{1221}{9900}$

$\therefore x=\dfrac{407}{3300}$
Multiple choice maths multiply and divide division trick division division of numbers

 $\displaystyle \frac{3x}{2}-\frac{x}{4}=2$. Find value of x

  1. $2$
  2. $\dfrac85$
  3. $4$
  4. $\dfrac45$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
$\cfrac { 3x }{ 2 } -\cfrac { x }{ 4 } =2$
$\cfrac { 6x-x }{ 4 } =2$
$\cfrac { 5x }{ 4 } =2$
$x=\cfrac { 4 }{ 5 } \times 2=\cfrac { 8 }{ 5 } $