Category: Q&A

Consider the factors of 2^6. There are 7 factors: 1, 2, 2^2, 2^3, ……, 2^6.
Similarly, for 3 there are 2 factors: 1, 3; and
similarly, for 643, there are 2 factors: 1, 643
So the total number of factors will be 7 x 2 x 2 – 2 (1 x 1 x 1 = 1, and 2^6 x 3 x 643 = 123456 need to be minus off) = 26 positive factors

A student wishes to walk from the corner X to the corner Y through streets as given in the street map as shown below.
He does not move to the left or downwards.
(i) Find the number of different routes from X to Y the student can take.
(ii) The student wishes to visit P on his way from X to Y as indicated in the diagram below. Find the number of different routes he can take.