Number sequences

The rule for this sequence 15, 20,25,30 is;

A sequence has 10,9,8,7,6

The rule for the sequence is;

12, 22, (a)   , 42, 52. The missing number is;

In the number sequence

105, 108, 111, 114

How do you find the next number in the sequence?

150, 155, 160, 165, (a)   . The missing number is;

1000, 2000, 3000, 4000, 5000. The rule for this sequence is

Given the numbers

500,550,600,650

This sequence starts with (a)  

Find the sequence

20, 40,60, ______100, ______

In the number sequence

400 350 300 250

The sequence starts with ______

To find the next number in the sequence. We....

Warrick makes a sequence of numbers , starting with 17. He subtracted 4 each time. What are the next 3 numbers in the sequence?