JAMB - Mathematics (1992 - No. 44)
A student has 5 courses to take from Mathematics and physics. There are 4 courses in Mathematics and 3 in Physics which he can choose his courses so that he takes exactly two courses in Physics?
48
12
10
7
คำอธิบาย
Total Mathematics courses = 4
Total Physics courses = 3
Courses to choose = 5
Courses in Physics to choose = 2
Courses in Mathematics to choose = 3
Mathematics = \(^{4} C_{3} = 4\)
Physics = \(^{3} C_{2} = 3\)
\(\therefore\) He can choose in 4 x 3 = 12 ways.