Two numbers are in the ratio 9.4. If 7
is added to each of the numbers, the
ratio becomes 5:3. Find the numbers.
Answers
Answer:
18 and. 8
Step-by-step explanation:
As the ratio is 9:4, let the numbers are 9a and 4a.
According to question: when 7 is added to both new numbers are 9a + 7 and 4a + 7.
= > ( 9a + 7 ) : ( 4a + 7 ) = 5:3
= > 3( 9a + 7 ) = 5( 4a + 7 )
= > 27a + 21 = 20a + 35
= > 27a - 20a = 35 - 21
= > 7a = 14
= > a = 14/7 = 2
Hence the numbers are :
9a = 9(2) = 18
4a = 4(2) = 8
EXPLANATION.
- GIVEN
Two number are in the ratio = 9:4
If 7 is added to each of the number, the ratio
becomes = 5:3
FIND THE NUMBER.
According to the question,
Let one number be = x
Let another number be = y
Case = 1
Two numbers are in the ratio = 9:4
=> x/y = 9/4
=> 4x = 9y
=> 4x - 9y = 0 ......(1)
Case = 2
if 7 is added to the number the ratio = 5:3
=> x + 7 / y + 7 = 5/3
=> 3 ( x + 7 ) = 5 ( y + 7 )
=> 3x + 21 = 5y + 35
=> 3x - 5y = 14 ...... (2)
From equation (1) and (2) we get,
multiply equation (1) by 3
multiply equation (2) by 4
we get,
=> 12x - 27y = 0
=> 12x - 20y = 14
we get,
=> - 7y = -14
=> y = 2
put the value of y = 2 in equation (2)
we get,
=> 3x - 5y = 14
=> 3x - 5(2) = 14
=> 3x - 10 = 14
=> 3x = 24
=> x = 8