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The average of the two-digit numbers, which remain the same when the digits interchange their positions, is- A. 33 B. 44 C. 55 D. 66 Answer: Option C Show Answer Solution(By Apex Team) $begin{array}{l}text{ Average }\ =Largefrac{11+22+33+44+55+66+77+88+99}{9}\ =Largefrac{(11+99)+(22+88)+(33+77)+(44+66)+55}{9}\ =Largefrac{4times110+55}{9}\ =Largefrac{495}{9}\ =55end{array}$

The 7th and 21st terms of an AP are 6 and -22 respectively. Find the 26th term A. -34 B. -32 C. -12 D. -10 Answer: Option B Show Answer Solution(By Apex Team) 7th term = 6 21st term = -22 That...

The average age of a husband and his wife was 23 years at the times of their marriage. After five years they have a one-year old child. The average age of the family now is.

15th term of A.P., x - 7, x - 2, x + 3, ........ is A. x + 63 B. x + 73 C. x + 83 D. x + 53 Answer: Option A Show Answer Solution(By Apex Team) $begin{array}{l}a_n=a+(n-1)times...

The average score of a class of boys and girls in an examination is A. The ratio of boys and girls in the class is 3 : 1. If the average score of...

In an engineering college the average salary of all engineering graduates from Mechanical trade is Rs. 2.45 lacs per annum and that of the engineering graduates from Electronics trade is Rs. 3.56 lacs per annum. The...

Average of ten positive numbers is $bar{x}$. If each number is increased by 10%, then $bar{x}$. A. Remains unchanged B. May decrease C. May increase D. Is increased by 10% Answer: Option D Show Answer Solution(By Apex Team) $begin{aligned}&Rightarrowfrac{x_1+x_2+ldots.+x_{10}}{10}=overline{x}\ &Rightarrow x_1+x_2+ldots+x_{10}=10overline{x}\ &Rightarrowfrac{110}{100}x_1+frac{110}{100}x_2+ldots.+frac{110}{100}x_{10}=frac{110}{100}times10overline{x}\ &Rightarrowfrac{frac{110}{100}x_1+frac{110}{100}x_2+ldotsldots+frac{110}{100}x_{10}}{10}=frac{11}{10}overline{x}\ &text{⇒...