Question
‘A’ is 40% more efficient than ‘B’. ‘A’ and
‘B’ work together for 8 days after which ‘A’ is replaced by ‘C’. ‘B’ and ‘C’ together take 4 more days to finish the work. If ‘A’ alone could’ve finished the whole work in 20 days, then find the time taken by ‘C’ to finish 60% work alone.Solution
Let the efficiency of 'B' be 'x' units/day So, efficiency of 'A' = x × 1.4 = '1.4x' units/day Total work = 20 × 1.4x = '28x' units So, work done by 'A' and 'B' together in 8 days = (x + 1.4x) × 8 = '19.2x' units So, remaining work = 28x - 19.2x = '8.8x' units So, efficiency of 'B' and 'C' together = 8.8x ÷ 4 = '2.2x' units per day So, efficiency of 'C' = 2.2x - x = '1.2x' units/day So, required time = (28x × 0.6) ÷ 1.2x = 14 days
The perimeters of 2 similar triangles ∆ABC and ∆PQR are 18 cm and 12 cm respectively. If PQ= 8 cm, then AB is?
∆ABC and ∆DEF are similar and their areas are respectively 16 cm2 and 64 cm 2 . If EF = 6 cm BC is?
In the given figure CD is parallel to AB then ∠y is?
The lengths of three medians in a triangles are 24 cm, 32 cm, 40 cm. What is the area of that traingle (in cm 2 )?
- Length of a chord in a circle of radius 'r' cm, is 14 cm and distance between chord and centre of the circle is 24 cm. Find the value of (4r - 60).
The radius of a circle is 13 cm, and the length of the chord is 10 cm. Find the distance between the chord and the centre of the circle.
The area of an equilateral triangle is 4√3 sq m. Its perimeter is
If median AD of an equilateral ∆ABC is 6 cm and G is centroid. Find AG?
What will be inradius of an equilateral triangle of side 4 cm?
The length of the each side of an equilateral triangle is 42√3. The area of incircle, (cm 2 ) is
Relevant for Exams:
