The sum of the squares of three consecutive natural numbers is 194. What is the sum of the numbers ? : āĻāĻā§ā§°āĻžāĻšā§ āĻĨāĻāĻž āϤāĻŋāύāĻŋāĻāĻž āϏā§āĻŦāĻžāĻāĻžā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻžā§° āĻŦā§°ā§āĻā§° āϝā§āĻāĻĢāϞ 194āĨ¤ āϏā§āĻ āϤāĻŋāύāĻŋāĻāĻž āϏāĻāĻā§āϝāĻžā§° āϝā§āĻāĻĢāϞ āĻāĻŋāĻŽāĻžāύ ??
Q. The sum of the squares of three consecutive natural numbers is 194. What is the sum of the numbers ? (āĻāĻā§ā§°āĻžāĻšā§ āĻĨāĻāĻž āϤāĻŋāύāĻŋāĻāĻž āϏā§āĻŦāĻžāĻāĻžā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻžā§° āĻŦā§°ā§āĻā§° āϝā§āĻāĻĢāϞ 194āĨ¤ āϏā§āĻ āϤāĻŋāύāĻŋāĻāĻž āϏāĻāĻā§āϝāĻžā§° āϝā§āĻāĻĢāϞ āĻāĻŋāĻŽāĻžāύ?)
Options:
(a) 24 (b) 27 (c) 21 (d) 30
Solution:
Let the three consecutive natural numbers be (āϧ⧰āĻž āĻšāĻāĻ, āĻāĻā§ā§°āĻžāĻšā§ āĻĨāĻāĻž āϤāĻŋāύāĻŋāĻāĻž āϏā§āĻŦāĻžāĻāĻžā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻž āĻšā§āĻā§): x, (x+1), (x+2)
According to the question : āĻĒā§ā§°āĻļā§āύ āĻ āύā§āϏ⧰āĻŋ:
x2 + (x+1)2 + (x+2)2 = 194
⇒ x2 + x2 + 2x + 1 + x2 + 4x + 4 = 194
⇒ 3x2 + 6x + 5 = 194
⇒ 3x2+6x = 189
⇒ x2+2x−63 = 0
⇒ (x+9)(x−7) = 0
⇒ x = 7
Numbers = 7, 8, 9
Sum = 7 + 8 + 9 = 24
Ans: 24