The average weight of a group of 75 girls was calculated as 47 kgs. It was later discovered that the weight of one of the girls was read as 45 kgs. Whereas her actual weight was 25 kg. What is the actual average weight of the group of 75 girls? **(Rounded off of two digits after decimal)**

# Topic: Average calculate in Maths

**Find the average of all prime numbers between 30 and 50.**

**The average age of 35 students in a class is 16 years. The average age of 21 students is 14. What is the average age of the remaining 14 students?**

**If the arithmetic mean of seventy-five numbers is calculated, it is 35. If each number is increased by 5, then the mean of new numbers is?**

**Four years ago, the average age of a family of four persons was 18 years. During this period, a baby was born. Today if the average age of the family is still 18 years, the age of the baby is?**

**The average of 12 numbers is 15 and the average of the first two is 14. What is the average of the rest?**

**The average of 6 numbers is 7. The average of three numbers of them is 5. What will be the average of the remaining numbers?**

**Find the average of the first 40 natural numbers.**

**The average of 4 positive integers is 59. The highest integer is 83 and the lowest integer is 29. The difference between the remaining two integers is 28. Which of the following integers is the highest of the remaining two integers?**

**Four years ago, the average age of A and B was 18 years. At present the average age of A, B, and C is 24 years. What would be the age of C after 8 years?**

**The average temperature for the first four days of a week is 40.2°C and that of the last four days is 41.3°C. If the average temperature for the whole week is 40.6°C, then the temperature on the fourth day is?**

The average age of a group of persons going for a picnic is 16 years. Twenty new persons with an average age of 15 years join the group on the spot due to which their average age becomes 15.5 years. The number of persons initially going for a picnic is

**The average of five numbers is 58. The average of the first two numbers is 48.5 and the average of the last two numbers is 53.5. What is the third number?**

**If the average marks of three batches of 55, 60, and 45 students respectively is 50, 55, and 60 then the average marks of all the students is?**

Ten years ago, the ages of the members of a joint family of eight people added up to 231 years. Three years later, one member died at the age of 60 years and a child was born during the same year. After another three years, one more member died, again at 60, and a child was born during the same year. The current average of this eight-member joint family is nearest to

In a cricket eleven, the average age of eleven players is 28 years. Out of these, the average ages of three groups of three players each are 25 years, 28 years, and 30 years respectively. If in these groups, the captain and the youngest player are not included, and the captain is eleven years older than the youngest player. What is the age of the captain?

**A school has 4 sections of Chemistry in Class X having 40, 35, 45 and 42 students. The mean marks obtained in Chemistry test are 50, 60, 55 and 45 respectively for the 4 sections. Determine the overall average of marks per student.**

**In a class there are 50 students. Their average weight is 45 kg. When a student leaves the class, the average is reduced by 100 g. Find the weight of the student who left the class.**

**The average of 11 results is 60. If the average of the first six results is 58 and that of the last six is 63, find the 6th result.**

**A shop for electronic goods is closed on Monday. The average daily sales for the remaining six days of the week is Rs.15,640 and the average sale on Tuesday to Saturday is Rs.14,124. The sales on Sunday are?**

**The average of 11 players in a cricket team is decreased by 2 months when two of them aged 17 years and 20 years are replaced by two new players. The average age of the new players is?**

**The average height of 35 girls in a class was calculated as 160 cm. It was later found that the height of one of the girls in the class was wrongly written as 144 cm, whereas her actual height was 104 cm. What is the actual average height of the girls in the class? (rounded off to 2 digits after decimal)**