Question
A train 270 metre long takes 36 sec to cross a man
running at a speed of 4 km/hr in the direction opposite to that of train. What is the speed of the train?Solution
Let the speed of the train be x Relative speed = (x + 4) km/hr ⇒ (x + 4) = (270 × 18)/(36 × 5) ⇒ (x + 4) = (4860)/(180) ⇒ x + 4 = 27 ⇒ x = 27 – 4 = 23 km/hr
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)}
Relevant for Exams:
