In a pond, lotus flower multiply its self after every 4 days. One lotus multiplies into two after four days, into 4 after 8 days, into 8 after 16 days and so on. If you see one lotus flower in a pond today, how many flowers will be there in the pond after 32 days.

The answer is 32 flowers. You can create the following table to see the pattern more clearly:

# of flower: 1, 2, 4, 8, 16

# of days: 4, 8, 16, 32

You are doubling the number of flowers to find the number of days. Or half the number of days is the number of flowers. So, in 32 days there are 16 flowers.