Answer:
Common difference is 3. And the first term is 64.
Step-by-step explanation:
The differnce between 21 and 10 is 11. So there are 11 unknown numbers in between. And the difference between 37 and 4 is 33. 33/11 is equal to 3. So the pattern is minus three. the first term is 9 terms before 37. 9 times 3 is 27. 37+27 is equal to 64. so the first term is 64
