Question

the nth term of a sequence is 2n+3 the nth term of a different sequence is 3n-4 work out the three numbers that are in both sequences and between 80 and 100

Answer 1

1st sequence: 5, 7, 9, 11, 13, etc

2nd sequence: -1, 2, 5, 8, 11, etc

2n+3≥80, 2n≥77, n≥39

1st sequence between 80 and 100: 81, 83, 85, 87, 89, 91, 93, 95, 97, 99 for n=39-47.

3n-4≥80, 3n≥84, n≥28

2nd sequence between 80 and 100: 80, 83, 86, 89, 92, 95, 98 for n=28-34.

Both series contain 83, 89, 95.