Question
My grandmother was 9 times older to me 18 years ago. She
would be 3 times of my age 9 years from now. 9 years ago, what was the ratio of my age to that of my grandmother?Solution
Let my age 18 years ago be x years My grandmother’s age at that time = 9 x years My present age = (x + 18) years My grandmother’s present age = (9 x + 18) years According to question 3(x + 18 + 9) = (9 x + 18 + 9) 3 x + 81 = 9 x + 27 9 x - 3 x = 81 – 27 6 x = 54 x = 9 Now, ratio of ages 9 years ago = (x + 18 -9 )/(9x +18 - 9) = (9 + 18 - 9)/(9 × 9 + 18-9 )=18/90 = 1:5
Evaluate: 360 ÷ [ {18 − (6×2)} × 5 ] + 72 − 33
(43)² - (28)² + (32)² = ?% of 2500
Evaluate:
√729 + √49 - √16 + 1/√64
What will come in place of (?) in the given expression.
12.5 + 7.75 - 3.6 = ?62 of 8 - 320 ÷ 4 = ?3 + 200
2(1/3) + 2(5/6) – 1(1/2) = ? – 6(1/6)
What will come in the place of question mark (?) in the given expression?
30% of 520 + 16% of 1500 = ? + 244
60% of 120 – ?% of 64 = 20% of 200
35% of 840 + 162 = ? – 25% × 300
20% of 240 + 18% of 200 = ?