Question
In a school with 400 students, the average of the age of
the boys is 16 years and that of the girls is 12 years. If the average age of the school is 14 years 9 months. Then find the number of girls in the school?Solution
Total number of students in school = 400 Let the number of Boys be ‘x. Then the number of girls in school = 400-x According to the question, x × 16 + (400 - x) × 12 = 400 × 14+9/12 16x + 4800 - 12x = 400 × 59/4 4x + 4800 = 5900 4x = 1100 x = 275 Number of girls = 400 - 275 = 125
What is the respective ratio of the number of people prefer to go Thailand in 2013, 2015 and 2017 to the number of people prefer to go Singapore in the ...

Study the given table to answer the question that follows.
The table shows the number of students who appeared in the 12th Board Examination f...

In the bar graph, in which year is the sum of the students f...
In an examination, a candidate is required to pass all six different subjects. The number of ways he can fail is:
What is the difference between the number of ASUS laptops sold in all the given years and the number of HP laptops sold in 2015, 2018 and 2020 together?
In 2012, no. of students appearing for IMS was 5%. However each year no of students increases by 10% in number. What will be the difference between the ...
In the year 2013, the student appearing in IMS is what percent of the students appearing in UIT and XLRI together in that year? ( approx )
...
Total number of HP laptops sold in 2015 and 2016 together is approximately what percent more of the total number of HP laptops sold in 2017 and 2018 tog...