Question 133
Six numbers are arranged in decreasing order. The average of the first five numbers is 30 and the average of the last five numbers is 25. The differences of the first and the last numbers is:
Solution
Let the numbers (in decreasing order) be $$a,b,c,d,e,f$$
Average of first 5 = 30
=> Sum of first 5 numbers = $$30\times5$$
=> $$(a+b+c+d+e)=150$$ --------------(i)
Similarly, sum of last 5 = $$25\times5$$
=> $$(b+c+d+e+f)=125$$ --------------(ii)
Subtracting equation (ii) from equation (i),
=> $$a-f=150-125=25$$
Thus, the differences of the first and the last numbers = 25
=> Ans - (C)
Get AI Help
Create a FREE account and get:
- Free SSC Study Material - 18000 Questions
- 230+ SSC previous papers with solutions PDF
- 100+ SSC Online Tests for Free
