A can do a piece of work in 9 days while B can do it in 12 days. A and B together can do the work in
A.
A and B together can do a piece of work :
The distance between two places A and B is 60 km. Two cars start at the same time from A and B, travelling at a speed of 35 km/hr and 25 km/hr respectively. If the cars run in the same direction, then they will meet after (in hours):
6.5
6.2
6
6.52
C.
6
As the cars run in the same direction
∴ Relative speed = (35 - 25) km/hr = 10 km/hr
Distance = 60 km
Required time:
The orthocentre of a triangle is the point where
the medians meet
the altitudes meet
the right bisectors of the sides of triangle meet
the bisectors of the angles of triangle meet
B.
the altitudes meet
A number is decreased by 10% and the resulting number is again decreased by 20%. What is the final percentage of decrease?
25%
26%
27%
28%
D.
28%
Net percentage decrease:
A mixture contains spirit and water in the ratio of 3 : 2. If it contains 3 litre more than water, the quantity of spirit in the mixture is
12 litre
10 litre
9 litre
8 litre
C.
9 litre
Let the quantity of spirit in the mixture = 3x
quantity of water in the mixture = 2x
According to the question,
3x - 2x = 3; x = 3 litre
∴ Quantity of spirit in the mixture = 3 x 3 = 9 litre
The sum of money that will yield ₹ 60/- as simple interest at 6% per annum in 5 years is
₹ 200/-
₹ 225/-
₹ 175/-
₹ 300/-
A.
₹ 200/-
S.I. = ₹ 60
Time (n)= 5 years
R = 6% p.a.
100 S.I. = PRT
100 X 60 = P x 6 x 5
P = ₹ 200/-
If the cost price of 25 pens is equal to the selling price of 20 pens, then the profit percent is:
20%
25%
15%
5%
B.
25%
Shortcut Method:
Required Profit percentage =
If x, y and z are real numbers such that (x - 3)^{2} + (y - 4)^{2} + (z - 5)^{2} = 0, then (x + y + z) is equal to
-12
0
8
12
D.
12
x - 3 = 0 ⟹ x = 3
y - 4 = 0 ⟹ y = 4
z - 5 = 0 ⟹ z = 5
∴ (x + y + z) = (3 + 4 + 5) = 12
A retailer gets a discount of 40% on the marked price of an article. The retailer sells it at the printed price. His gain percent is
40%
55%
75%
C.
Let the marked price of article be Rs. 100
∴ Cost price of an article for the retailer
Selling price of article would be the (marked price) Rs. 100
∴ Required gain percentage