I am a common factor of 40 and 50. I am a multiple of 2 and 10. I am greater than 7. What number am I?
Factors of 40: 1, 2, 4, 5, 8, 10, 20, 40
Factors of 50: 1, 2, 5, 10, 25, 50
Highest common factor of 40 and 50: 10
Multiples of 2: 2, 4, 6, 8, 10
Multiples of 10: 10
Lowest common multiple of 2 and 10: 10
The number is 10.
Answer(s): 10