10+10=20, 15+5=20 Those are both addition sentences that have a sum of 20.
Answer:

Step-by-step explanation:



Answer:
4.9 is decimal form.
Step-by-step explanation:
4 9/10
Solve :
4 9/10
= 49/10
= 4.9
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
I think it would be 35 combinations but I may be wrong