Sequences - math puzzle
What are the next numbers in the following sequences?
a: 77, 143, 221, 323, 437
b: 1, 5, 32, 288, 3413
c: 827, 23, 11, 6, 3
d: 2, 3, 5, 11, 31
e: 100, 121, 144, 202, 244
a: 77, 143, 221, 323, 437
b: 1, 5, 32, 288, 3413
c: 827, 23, 11, 6, 3
d: 2, 3, 5, 11, 31
e: 100, 121, 144, 202, 244
Spy satellite - math puzzle
A spy satellite circles around the earth in 1.57 hours. Can you tell within 3 seconds how much time it takes until the satellite has made 24 revolutions? |
Bob and John - math puzzle
Bob and John form a team together. Bob is as old as John will be when Bob is twice as old as John was when Bob was half as old as the sum of their current ages. John is as old as Bob was when John was half as old as he will become over ten years.
How old are Bob and John?
How old are Bob and John?