Question
A, B, and C together can do a work alone in 18 days, 32
days, and 60 days respectively. A alone starts the work and work for 3 days and leaves the work, then B alone does the work for 8 days and leaves the work. If remaining work is done by C alone then for how many days has C worked?Solution
Total work = LCM of 18, 32 and 60 = 1440 units Unit per day of A = 1440/18 = 80 Unit per day of B = 1440/32 = 45 Unit per day of C = 1440/60 = 24 Units of work done by A in 3 days = 80 × 3 = 240 units Units of work done by B in 8 days = 45 × 8 = 360 units Remaining work = 1440 – (240 + 360) = 840 units So, C has worked for 840/24 = 35 days
The lateral surface area of a regular tetrahedron is 75√3 cm². Determine the volume of the tetrahedron.
Find the area of sector of a circle whose radius is 21 cm and angle subtended by the sector at centre of circle is 45 ° .
The perimeter of a rectangle is 64 cm. The side of a square is equal to the average of the rectangle’s length and breadth. Find the area of the square...
- If the edge of the cube is increased by 30%, then find the percentage increase in the volume of the cube.
If the length of a rectangle is increased by 25% and its breadth is decreased by 15%, then the area of the rectangle will be increased or decreased by h...
The radii of two solid right circular cylinders are 11 cm and 9 cm respectively and their heights are (h+1) cm and (2h+1) cm respectively. If the areas ...
The volume of a cone is 128π cubic centimeters. If the radius of the base is 4 cm, find the height of the cone.
A cone has a radius of 5 cm and a slant height of 13 cm. Find the total surface area of the cone.[Take π = 3.14 ]
If x4 – 62x2 + 1 = 0, then a value of x 3 + x -3 can be:
The base of a triangle is 18 cm and height is 15 cm. The height of another triangle of double the area having the base 27 cm is: