Question

15) A, B and C can do a piece of work in 6 days, 12 days and 24 days respectively.If three of
them work together, in how many days they will complete the work?
16) A wooden box 2 m long, 68 cm wide and 30 cm high is packed with plastic blocks 10
cm long, 8 cm broad and 5cm high. How many blocks are there in the box?
17) An article marked Rs.2000 was sold at a discount of 20% If the C.P of the article was
Rs.1200,find the profit or loss%
18) Add 6 y? - 6y + 10 to the quotient of (3y + 13y2 + 2y - 8) when divided by (y + 4)
19) Factorise : x2 +3x - 40.
(OR)
Factorise : 4x² + 8x - 5.
12x-1
20) Find the value of x, when
1) The area of a trapezium is 329 cm'. If one of its parallel sides is 5cm longer than the
other side and its altitude is 14cm. Find the length of the parallel sides.
2) The angles of a quadrilateral are in the ratio 5: 6:10:15. Find the angles of the
quadrilateral.

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Answer 1

Answer:

Step-by-step explanation:

15

total work done by them = lcm(6,12,24) = 24

work done by A everyday = 24/6 = 4 hours

work done by B everyday = 24/12 = 2 hours

work done by C everyday = 24/24 = 1 hours

TOTAL work done by them in = 4+2+1 = 9 days