Answer: 260
Step-by-step explanation: ok we know that there a 5 time increase (500 percent), meaning all we need to do is to divide this year number by 5 to find out last year number. 1300/5 is 260.
From the slope form of a line;

y-b=bx-ab
y=bx-ab+b
y=bx-b(a-1)