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The average weight of 11 person among 12 person is 95kg . The weight of the 12 th person is 33 more that the average of all 12 , find the weight of the 12th person ?

A128

B131

C151

D145

Answer:

B. 131

Read Explanation:

  • Step 1: Calculate the total weight of the first 11 persons.

    • Given, the average weight of 11 persons = 95 kg.

    • Using the average formula, the Sum of weights of 11 persons = Average atimes Number of persons.

    • So, Sum of weights of 11 persons = 95 kg atimes 11 = 1045 kg.

  • Step 2: Define variables for the overall average and the 12th person's weight.

    • Let 'X' be the average weight of all 12 persons.

    • Let 'W' be the weight of the 12th person.

  • Step 3: Formulate the relationship involving the 12th person's weight.

    • According to the problem, the weight of the 12th person (W) is 33 kg more than the average of all 12 persons (X).

    • This can be written as: W = X + 33.

  • Step 4: Express the overall average in terms of total weight.

    • The Sum of weights of all 12 persons = Sum of weights of 11 persons + Weight of 12th person.

    • So, Sum of weights of all 12 persons = 1045 + W.

    • The average weight of all 12 persons (X) will be: X = (1045 + W) / 12.

  • Step 5: Solve the equations to find the weight of the 12th person.

    • Substitute the expression for X from Step 4 into the equation from Step 3:

    • W = [(1045 + W) / 12] + 33

    • To eliminate the fraction, multiply the entire equation by 12:

    • 12W = (1045 + W) + (33 atimes 12)

    • 12W = 1045 + W + 396

    • 12W - W = 1045 + 396

    • 11W = 1441

    • Finally, solve for W: W = 1441 / 11 = 131 kg.


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തുടർച്ചയായ മൂന്നു ഒറ്റ സംഖ്യകളുടെ തുക 33 ആയാൽ ഏറ്റവും വലിയ സംഖ്യ ഏത്?