Question
A, B and C can complete a work in 10 days, 20 days and
30 days respectively. A and C started the work together and they both work for 6 days. If the remaining work is completed by B and D in 3 days, then find the number of days taken by D to complete (1/5)th of the same work.Solution
Let the total work (LCM of 10, 20 and 30) = 60 units Efficiency of A = 60/10 = 6 units/day Efficiency of B = 60/20 = 3 units/day Efficiency of C = 60/30 = 2 units/day Work done by A and C together in 6 days = 6 × (6 + 2) = 48 units Remaining work = 60 – 48 = 12 units Efficiency of D = (12/3) – 3 = 1 unit/day Number of days taken by D to complete (1/5)th of the same work = (60/5)/1 = 12 days
The length of a plot is three times its breadth. A playground measuring 216 square metres occupies half of the total area of the plot. What is the lengt...
Calculate the perimeter of a square when the area of a circle that circumscribes it is 486 square centimeters. (Assume π = 3 for calculations.)
If two complementary angles are in the ratio of 3:2, find the greater angle.
The ratio of length to breadth of a rectangle is 6:9. If the sum of the length and breadth of the rectangle is 45 cm, then find the area (cm 2
Angle bisectors of Q and R meet at point S, inside the triangle PQR. If angle QSR = 120Ëš , then the measure of angle P is:
Find the approximate volume of a right circular cone having diameter 14 cm and height 3cm.(Take pie = 3.14.)
The length, breadth and height of a solid cuboidal box are in the ratio 7 : 5 : 3 and its total surface area is 11502cm2. Its breadth is:
The length of a rectangle is 18 cm more than the side of a square. The perimeter of the square is 72 cm. If the breadth of the rectangle is 12 cm less t...
If b sin θ = a, then sec θ + tan θ = ?
- The cost of fencing a rectangular field at the rate of Rs. 13/metre is Rs. 1560. The ratio of the length to the breadth is 7:5. Find the area of the field.
Relevant for Exams:
