Question

Bala had 240 cards and Tom had 780 cards.
After Tom gave some cards to Bala, Bala had twice as many
cards as Tom.
How many cards did Tom give to Bala?

Answer 1

let the given cards be x

therefore total cards with bala =240+x

cards with tom =780-x

2(240+x) = 780-x

420+2x= 780-x

2x+x = 780-420

3x = 360

x = 360/3

x = 120

∴cards with bala = 240+120=360

cards with tom = 780 - x

                          = 780 -120

                         =660

pls mark the brainiest  ........................

Answer 2

Answer:

Concept:

Lending certain number of cards to Bala under certain constraint.

Step-by-step explanation:

Given:

Number of cards with Bala, $n(B)$ = 240

Number of cards with Tom , $n(T)$=780

To find:

Number of cards given to Bala by Tom

Solution:

• Let $x$ be the total number of cards.

    $x=n(B)+n(T)$

    $x=240+780$

i.e. $x=1020$

• Let $y$ be the number of cards lend by Tom to Bala. After giving $y$  cards to Bala , Tom left with $780-y$ cards .

                          $n(T)=780-y$       ⇒   A

• By given statement after getting $y$ cards from Tom , Bala has twice as many cards as Tom.

                      i.e. $n(B)=2\times n(T)$   ⇒  B

             and        $n(B)=240+y$

•    Substitute A in B,

                  $n(B)=2\times(780-y)$

• Equating $n(B)$ ,

           $240+y=2\times(780-y)$

          $240+y=1560-2y$

            $y+2y=1560-240$

                   $3y=1320$

                     $y=\frac{1320}{3}$

                      $y=440$

Hence, Tom give $440$ cards to Bala.

 #SPJ3