Question
If the arithmetic mean of x, x + 3, x + 6, x + 9 and x +
12 is 10, then x = ?Solution
ATQ,
We are given that the arithmetic mean of the numbers: x, x+3, x+6, x+9, x+12 is 10. To find the sum add all the numbers: x+(x+3)+(x+6)+(x+9)+(x+12) = 5x+(3+6+9+12) = 5x+30 By using the arithmetic mean formula:- So,
Multiply both sides by 5: 5x+30 = 50 Subtract 30: 5x = 20 ⇒ x= 4
(√ 121 x 41) + (3√343 x √289 ) = ? x 19  Â

7, 8, 12, 21, 37, ?
Evaluate: 72 ÷ 6 × (5 + 1) − 8² + 10
What will come in the place of question mark (?) in the given expression?
(30 × 5 + 20) × 2 = ?
What will come in the place of question mark (?) in the given expression?
737 + 149 - ?²- 367 = 14 X 25(√ 1444 ÷ 5) × 3.25 = ?
522 + 160% of 80 - 130 = ? X 13Â
54% of 250 = 6 × 21 + √?
300% of (3341 – 471) = ? × (√4225/195)