Question
A seller marked the price of an item at Rs. 3,000. The
seller gave successive discounts of (y + 3)% and (y - 3)% to a customer. If the customer paid Rs. 2,430 for the item, then find the value of 'y'.Solution
ATQ; SP of the item = 3000 × (1 - (y + 3)/100) × (1 - (y - 3)/100) = 2430 or, {(100 - y - 3)/100} × {(100 - y + 3)/100} = 2430/3000 or, (97 - y) × (103 - y) = (2430/3000) × 100 × 100 or, 97 × 103 - 97y - 103y + y² = 8100 or, y² - 200y + 9991 - 8100 = 0 or, y² - 200y + 1891 = 0 or, y² - 10y - 190y + 1891 = 0 or, y × (y - 10) - 189 × (y - 10) = 10 or, (y - 10) × (y - 189) = 10 So, y = 10 or y = 189 But, y = 189 is not possible because the discount cannot be more than 100%. Therefore, y = 10
30.01 × √1023 + 196 = ? 2 – 287
70.008% of 399.98 + ?% of 399.999 = 80.105% of 599.998
? = 26.08 + 18.99 × 25.07
A bag contains 25 white and some black balls. If the probability of drawing a black ball from the bag is thrice that of drawing a white ball, fin...
 15.78% of (287 + 302) + 12³ = ?% of 170 + 8 × 14 + 3²Â
40 × 55.96 ÷ 7 – 20% of 699.81 + 63 = ? - (11479.50 ÷ 7)
A certain sum of money invested at R% p.a. fetches a compound interest (compounded annually) of 1620 and simple interest of Rs.1500 at the end of 2 year...
4650.12 ÷ √8648.88 + √27.08 * √1727.85 = ? – 609.10 ÷ 87.07                     Â
...(439.98 ÷ 10.99) × 23.98= ? × (23.98) 2 ÷ 47.98
29.88% of 3599.90 + 5/12 of 2399.81 – 34.81% of 1200.18 = ?