Tag: equations from statements

Questions Related to equations from statements

Multiple choice maths calculations and mental strategies 1 equations from statements forming equations from statements writing mathematical statements

A game is played by three players. The loser has to triple the money of each of the other players has. Three games are played and each one losses a game. At the end all have the same amount namely $Rs.\ 54$. The amount the first loser has at the begining is

  1. $Rs.\ 120$
  2. $Rs.\ 112$
  3. $Rs.\ 110$
  4. $Rs.\ 90$
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice maths calculations and mental strategies 1 equations from statements forming equations from statements writing mathematical statements

If a number, when divided by $4$, is reduced by $21$, the number is:

  1. $18$
  2. $20$
  3. $28$
  4. $38$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Let $x$ be the number.
If a number is divided by the $4$ the expression becomes $\dfrac{x}{4}$
If a number, when divided by $4$, is reduced by $21$, then the equation is
$\dfrac{x}{4}=x-21$
$\Rightarrow\,\dfrac{x}{4}-x=-21$
$\Rightarrow\,\dfrac{x-4x}{4}=-21$
$\Rightarrow\,-3x=-21\times 4$
$\Rightarrow\,x=\dfrac{21}{3}\times 4=7\times 4=28$
$\therefore\,$,the number is $28$
Multiple choice maths calculations and mental strategies 1 equations from statements forming equations from statements writing mathematical statements

The product of two numbers is 1296. If one number is 16 times the other, then the two numbers are 

  1. 144, 25

  2. 81, 49

  3. 144, 9

  4. none of these

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

Let the first number be $x$. Then, other number is $16x$.


Now, $x \times 16x =1296$

$16x^2=1296$
$x^2=81$
$x=9$
$16x=16\times 9=144$

Thus, the two numbers are $9$ and $144.$