Question
7 years ago, the average age of a family of four persons
was 30 years. In between these 7 years the family adopted a girl. Now at present the average age of the family is same as it was 7 years ago. Find the present age of the girl.Solution
Sum of the present age of the family excluding girl = 4 × (30 + 7) = 148 years Sum of the present age of the family including girl = 5 × 30 = 150 years Present age of the girl = 150 – 148 = 2 years
Solve for x in the equation: 3(x + 2) + 2(2x - 5) = 5x + 9
If x = 19, then the value of x5 - 20x4 + 20x3 - 20x2 + 20x - 1 is
Given a triangle with two sides measuring 12 cm and 16 cm, which of the following cannot be a possible length for the third side?
The mean age of 30 students was calculated as 15 years. However, it was later discovered that one student's age was mistakenly entered as 15 years inste...
In a triangle ABC, a point D lies on AB and points E and F lie on BC such that DF is parallel to AC and DE is parallel to AF. If BE = 4 cm. EF = 6cm. th...
If a = 32, b = c = 31, then find the value of a 3 + b 3 + c 3 – 3abc.
If x3 + y3 = 9 and x + y=3 then the value of x4 + y4 is:
105, 111, 123, 141, ?, 195
Let {x + (1/x)} = 4, then Determine the value of {x² + (1/x²)}
