10C0 + 9C1 + 8C2 + 7C3 + 6C4 + 5C5
Garima takes the underground train to work and uses an escalator at the railway station. If Garima runs up 8 steps of the escalator, then it takes her 30.0 seconds to reach the top of the escalator. If she runs up 15 steps of the escalator, then it takes her only 12.5 seconds to reach the top.
How many seconds would it take Garima to reach the top if she did not run up any steps of the escalator at all?
A network of 20 x 10 squares is given to you.
Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?
Find amounts of money that can be made up in two ways so that one set of coins has twice as many coins as the other (but not using only 1c and 2c coins). e.g. 71c is 50c, 20c, 1c (3 coins) or 20c, 20c, 20c, 5c, 5c, 1c (6 coins)