Three numbers are in the ratio 2 : 3 : 4. The sum of their cubes is 33957. Find the
numbers.
Answers
Given:
- Three numbers are in ratio 2:3:4.
- The sum of their cubes is 33957.
To Find:
- The three numbers.
Answer:
Let us take the given ratio be 2x:3x:4x .
Now , Sum of these numbers = 2x + 3x +4x = 9x.
Also , cube of these numbers
- (2x)³=8x³.
- (3x)³=27x³
- (4x)³=64x³.
Atq ,
=> 8x³+27x³+64x³=33957.
=> 99x³=33957
=> x³=33957/99
=>x³ = 343.
=> x = ³√343
=> x = 7.
Hence,
- First Number = 2x = 14.
- Second number = 3x = 21.
- Third Number = 4x = 28.
The 3 numbers are : 0.3,0.45,0.6
⇛The question says there are three numbers but with a specific ration what that means in that once we pick one of the numbers the other two are know to us through the rations we can therefore replace all 3 of the numbers with a single variable:
2: 3: 4 ⇛ 2x × 3x × 4x
⇒now, no Matter what we chose for c we get the three numbers into the ratios specified we are also told the sum of the cubes of these three numbers which can write :
⇛Disturbing the powers across the fact is using
⇛So the 3 numbers are