19. What must be subtracted from each term of
ratio 3:7, so that the ratio becomes 2:5?
Answers
Answer:
3-x/7-x=2/5
(7-x) *2=(3-x) 5
14-2x=15-5x
3x=1
x=1/3
To find:
✠ What must be subtracted from each term of ratio 3:7, so that the ratio becomes 2:5 ?
Solution:
Let's understand the concept first! First we will assume that x be the number which must be subtracted from each term of ratio 3:7, so that the ratio becomes 2:5, which means that we will minus x from the ratio of 3 well as 7, then it is equivalent or equal to ratio of 2:5. Therefore, forming an adequate equation and then doing required calculations, we will find the value of x which will be equal to the number which must subtracted from each term of ratio 3:7, so that the ratio becomes 2:5.
Let's find it...✧
Let the number to be substracted from the each term be x.
According to the question,
➛ ( 3 - x )/( 7 - x ) = 2/5
By cross-multiplication method,
➛ 5( 3 - x ) = 2( 7 - x )
➛ 15 - 5x = 14 - 2x
➛ 15 - 14 = - 2x + 5x
➛ 3x = 1
➛ x = 1/3
∴ 1/3 to be substracted from each term of ratio 3:7, so that the ratio becomes 2:5.
Verification:
L.H.S
➤ ( 3 - 1/3 )/( 7 - 1/3 )
➤ ( (9 - 1)/3 )/( (21 - 1)/3 )
➤ ( 8/3 )/( 20/3 )
➤ 8/3 × 3/20
➤ 8 × 1/20
➤ 8/20
➤ 4/10
➤ 2/5
= R.H.S
Hence Proved!!
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