The tangent ratio is used for right triangles
The correct answer is w=8x2 - y
18 divided by 30 is 0.6. So I would say that B, or 0.6, is the correct answer.
The calculation uses the accumulated daily balance method (ADB).
We assume the statement is based on calendar month (rare!).
George owes $500 from beginning to end of June, so 30 days out of 30.
Interest accrued is 500*0.013*30/30=$6.50.
He also owes $2000 from June 12 to June 30, so 19 days inclusively.
Interest accrued is $2000*.013*(19/30)=16.47
Total interest at the end of the month=$6.50+$16.47=$22.97
