#7700. The average of x, y, and z is 30, and the average of x and y is 20. What is the value of z?

]]>#7699. Find the average of the two-digit numbers, which remain the same when the digits interchange their positions.

]]>#7698. The average weight of M, N, and O is equal to 65 kilograms. The average weight of M and N is equal to 69.5 kilograms. The average weight of N and O is 66.5 kilograms. What is the weight of N?

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#7697. The mean of 15 different natural numbers is 13. Find the maximum value of the second largest of these numbers.

]]>#7696. The average height of 16 students is 142 centimeters. If the height of the teacher is included, the average height increases by 1 centimeter. Find the height of the teacher.

]]>#7695. The present age of Raechel is one fourth of that of her father. After 6 years, the father's age will be twice the age of Kevin. If Kevin celebrated fifth birthday 8 years ago, what is Raechel's present age?

]]>#7694. The average of 9 consecutive positive integers is 63. Find the product of the largest and smallest integers.

]]>#7693. The average weight of 19 men is 74 kilograms and the average weight of 38 women is 63 kilograms. What is the average weight (rounded off to the nearest integer) of all the men and women together?

]]>#7692. The average of four consecutive odd numbers P, Q, R, and S respectively (in increasing order) is 104. What is the sum of P and S?

]]>#7691. What will be the average of the following set of scores (rounded off to the nearest integer)?

62, 76, 42, 84, 21, 47, 28.

#7690. The average of five numbers is 34.4. The average of the first and the second number is 46.5. The average of the fourth and the fifth number is 18. What is the third number?

]]>#7689. The average height of 27 persons was recorded as 162 centimeters. If the height of Samson was deleted from the observation, the average height reduced by 1 centimeter. What was Samson's height?

]]>#7688. The average of four consecutive even numbers P, Q, R, and S respectively (in increasing order) is 51. What is the product of P and R?

]]>#7687. The average of 9 integers is found to be 11. But after the calculation, it was detected that, by mistake, the integer 23 was copied as 32, while calculating the average. After the due correction is made, find the new average.

]]>#7686. The average of first three numbers is double of the fourth number. If the average of all the four numbers is 12, find the 4th number.

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