PSLEBooks in a class library are grouped according to the following four types: Science, Mystery, Romance, and History. The bar graph shows the number of books of each type in the class library.
- What percentage of books in the class library was of the Science type?
- There were 44 students in the class. Every student in the class took two or four books home to read over the weekend. No book was left in the classroom. How many students took four books home?
(a)
Total number of books
= 28 + 16 + 26 + 30
= 100
Percentage of books that was Science
=
28100 x 100%
=
725 x 100%
= 28%
(b)
Number of students who took 4 books |
Number of books taken |
Number of students who took 2 books |
Number of books taken |
Total number of books taken |
44 |
44 x 4 = 176 |
0 |
0 |
176 |
43 |
43 x 4 = 172 |
1 |
2 |
174 |
Difference in the number of books if 1 more student takes 2 books instead of 4
= 176 - 174
= 2
Total difference in the number of books taken
= 176 - 100
= 76
Number of students who took two books home
= 76 ÷ 2
= 38
Number of students who took four books home
= 44 - 38
= 6
Answer(s): (a) 28%; (b) 6