The following table gives the percentage of total students and also girl…
2020
The following table gives the percentage of total students and also girl students enrolled in five schools (A-E). The total number of students is 4500, while the total number of girl students is 2000. Based on the data of the table, answer the questions that follow.
School Name | % of Total Students Enrolled | % of Girl Students Enrolled |
|---|---|---|
A | 20% | 15% |
B | 30% | 35% |
C | 25% | 12% |
D | 15% | 25% |
E | 10% | 13% |
Ques: The total number of boys enrolled in schools C, D and E is
- A.
965
- B.
1250
- C.
1021
- D.
1325
Attempted by 1 students.
Show answer & explanation
Correct answer: B
Concept: To convert a "percentage of total students" figure into a headcount, apply it to the grand total of students (4500); to convert a "percentage of girl students" figure into a headcount, apply it to the grand total of girl students (2000) -- the two percentage columns use two different bases. The number of boys in any school is then its total-student headcount minus its girl-student headcount, and boys across several schools are found by summing each school's boys figure.
Total students per school (% of total students × 4500): School A = 20% × 4500 = 900; School B = 30% × 4500 = 1350; School C = 25% × 4500 = 1125; School D = 15% × 4500 = 675; School E = 10% × 4500 = 450.
Girl students per school (% of girl students × 2000): School A = 15% × 2000 = 300; School B = 35% × 2000 = 700; School C = 12% × 2000 = 240; School D = 25% × 2000 = 500; School E = 13% × 2000 = 260.
Boys per school = total students − girl students: School C = 1125 − 240 = 885; School D = 675 − 500 = 175; School E = 450 − 260 = 190.
Boys in schools C, D and E = 885 + 175 + 190 = 1250.
Cross-check: As an independent check, the total-student percentages for C, D and E add to 25% + 15% + 10% = 50% of 4500 = 2250, and the girl-student percentages for the same three schools add to 12% + 25% + 13% = 50% of 2000 = 1000, so boys in C, D and E = 2250 − 1000 = 1250, matching the school-by-school total. Also, total boys overall = 4500 − 2000 = 2500, and boys in schools A and B alone = 600 + 650 = 1250, so the remainder 2500 − 1250 = 1250 confirms the figure again.
Result: 1250.