Question
The average of two numbers is 25, and the square root of
their product is 20. What is the difference between the two numbers?Solution
Let the two numbers = a and b         Given – Average of numbers = (a + b)/2 = 25 a + b = 50       ...(I) square root of these numbers = √  ab = 20 squaring both sides ab = 400 So now – (a + b)2 = (a- b)2 + 4ab (50)2 – 4 ×400 = (a-b)2 (a-b)2 =2500- 1600 = 900  a – b = 30.
50 62 ? 96 126 138
...81, 90, 108, 135, 171, ?
13, 14, 18, 27, 43, ?
2187, 1458, 972, ?, 432, 288
219 365 511 ? 803 949
...5Â Â Â Â 13Â Â Â Â 36Â Â Â Â 145Â Â Â Â Â 719Â Â Â Â 4321
1 9 64 255 755 1835
...1001, 728, 513, 342, 217, ?
729 512 343 216 125 ?
...43Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 44Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 48Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ...