Remark
Whatever the original price, he gets 70% in the first instance.
He gets 80% in the second instance.
He gets 90% in the third instance
His total income is 240 dollars.
Let the original price be x
Equation
70%x + 80%x +90%x = 240
70% = 0.7 ; 80% = 0.8 ;90% = 0.9
Solution
0.7x + 0.8x + 0.9x = 240 Take out x as a common factor and add the decimals.
x (0.7 + 0.8 + 0.9) = 240
2.4x = 240 Divide both sides by 2.4
x = 240/2.4
x = 100
So the watches should have brought in 3*100 = 300 dollars.
He only brought in 240 dollars.
He lost 300 - 240 = 60 dollars.
The answer is B.
