If (a - b) : (a + b) = 1 : 11, find the ratio (5a + 4b + 15) : (5a - 4b +3) .
The given problem is based on the ratio of two numbers.
Answer: If (a - b) : (a + b) = 1 : 11, then the ratio (5a + 4b +15) : (5a - 4b + 3) = 5 : 1
Let us find (5a + 4b + 15) : (5a - 4b + 3).
Explanation:
The ratio formula for any two quantities say a and b is given as, a : b = a / b
Given that, (a - b) : (a + b) = 1 : 11
(a - b) / (a + b) = 1 /11
11(a - b) = 1(a + b) --------> By cross multiplication
11a - 11b = a + b
11a - a = 11b + b
10a = 12b --------> Divide by 2 on both sides.
5a = 6b
Now let us move on to (5a + 4b + 15) : (5a - 4b + 3)
(5a + 4b +15) / (5a - 4b +3)
(6b + 4b +15) / (6b - 4b +3)
(10b + 15) / (2b + 3)
5(2b + 3) / (2b + 3) --------> Taking 5 common in the nuemerator.
5/1
= 5 : 1
So, (5a + 4b + 15) : (5a - 4b + 3) = 5 : 1
Thus, ratio (5a + 4b + 15) : (5a - 4b + 3) is equivalent to 5 : 1 .
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