Bi weekly is a check every 2 weeks, so she would get 26 checks per year.
Monthly would be 12 checks per year.
When she gets paid monthly her pay increased by $2,800 each check.
Let x be one bi-weekly paycheck.
12(x+2800) = 26x
12x +33600 = 26x
Subtract 12x from both sides
33600 = 14x
Divide both sides by 14:
x = 33600/14
x = 2400
Her pay increased by 2800 each period:
2400 + 2800 = 5200 per check.
5200 x 12 months = 62400
Her annual salary is $62,400