Question
In an examination, the average marks obtained by the
students is 75. After correcting the quantitative mistakes, the average of 100 students is reduced to 60 from 75 and the overall average of the student is reduced to 70. Then find the total number of students who participated in that examination.Solution
Let the total number of students be x Average marks obtained by the students = 75 Total marks = 75 x After correcting the quantitative mistakes the average decreased by (75-60) = 15 marks Total reduction = 15 × 100 = 1500 Now According to the Question, (75x-1500)/x = 70 70 x = 75 x – 1500 x = 300 Total number of students = 300
A group of 20 boys can complete a task in 15 days. Similarly, 24 girls can finish the same task in 20 days. If the ratio of the e...
The mean of 5 observations is 10 and their standard deviation is 4. Each observation is multiplied by 3 and then increased by 5. Find the new mean and t...
A store sells 3 products: A, B, C. In a month it sells:
A → 240 units
B → 180 units
C → 300 units
...
In the given question, the given two series following the same pattern, then find the pattern used in the 1st series and use the pattern to find the unk...
Pipe X can fill a tank on its own in 12 hours, while Pipe Y can fill the same tank individually in 20 hours. Both pipes X and Y o...
A person 'P' borrowed some money from a friend who lends under a unique interest structure. For the first two years, the annual i...
'O' is the incentre of △ABC. Given that ∠ABC = 64° and ∠BCA = 96°, determine the measure of ∠BOC.
A car covers the first 40 km of a journey at 60 km/h and the next 60 km at 90 km/h. What is the average speed for the entire journey?
The average weight of 14 students in a class is 30 kg. Two more students weighing 20 kg and 24 kg join the class. What is the average weight of the clas...
Relevant for Exams:
