Let the smaller number be x.
The larger number is 1 more than 3 times the smaller number; in numbers this is: 3x + 1.
Their sum is 15, so subtracting x from 3x + 1 will be equal to 15. Your equation is: 15 = (3x + 1) - x
Solve 15 = (3x + 1) - x algebraically for x, and then plug x into 3x + 1 to find the larger number.
15 = (3x + 1) - x
15 = 3x + 1 - x
15 = 2x + 1
14 = 2x
7 = x
3x + 1
3(7) + 1
21 + 1
22
Finally, check all work.
22 - 7 = 15
7(3) + 1 = 22
Answer:
The smaller number is 7 and the larger number is 22.
