Give the smaller number a name. Call it ' Q '.
The numbers are consecutive, so the larger number is (Q + 1) .
Five times the smaller number is 5Q .
Three times the bigger number is 3(Q+1) = 3Q+3 .
The problem says that when you add all this up ... 5Q + (3Q+3) ... you get 579.
5Q + 3Q + 3 = 579
Clean up the left side:
8Q + 3 = 579
Subtract 3 from each side:
8Q = 576
Divide each side by 8 :
Q = 72
The smaller number is 72, and the larger number is 73.