The half life of `._(90)Th^(225)` is 8 minutes How many half lives are there in 2 hours ? How long would you have to wait before there is less than 1 % of `._(90)Th^(225)` left in the sample ?
1 Answers
In a triangle ABC, the altitude from A is not less than BC and the altitude from B is not less than AC. The triangle
Correct Answer - A Given `c sin B ge a` `rArr sin C sin B ge sin A` and `a sin C ge b` `rArr sin C sin A ge sin...
2 Answers 3 views
if letters of the word MATHEMATICS are arranged then the probability that C come before E,E before H ,H before I and I before S
Correct Answer - C `(c )` The total number of arrangments is `(11!)/(2!2!2!)=(11!)/(8)` The number of arrangements in which `CE,H,I,S` appear in that order `"^(11)C_(5)(6!)/(2!2!2!)=(11!)/(8*5!)` `:.` Required Proability `=((11!)/(8*5!))/((11!)/(8))=(1)/(120)`
2 Answers 1 views
i. Minutes are prepared before the meeting. ii. Resolution is a proposal put before a meeting for discussion.
i. Minutes are prepared after the meeting. ii. Motion is a proposal put before a meeting for discussion. iii. Polling papers are used for voting by-poll. iv. A Resolution is a final decision taken in the meeting. v. The...
2 Answers 1 views
Machine A can produce 6 items per hour and machine B can produce 11 items per hours. If machine A works for x hours and B works for y hours in a day a
Correct Answer - `6x + 11y le 200`
2 Answers 1 views
Pipe A can fill a tank in 40 minutes . Pies B can empty the tank in 30 minutes . If both the pipes are opened simultaneously when tank is half full, t
Correct Answer - empty
2 Answers 1 views
300 men can construct a200m long wall in 12 days working 8 hours a day. In how many days can 120 men construct 180 m long wall working 9 hours per day
\(\frac{M_1D_1H_1}{W_1}=\frac{M_2D_2H_2}{W_2}\) M1 = 300, D1 = 12, H1 = 8, W1 = 200 M2 = 120, D2 = ? H2 = 9, W2 = 180 \(\frac{300\times12\times8}{200}=\frac{120\times D\times7}{180}\) D = 24 days
2 Answers 1 views
Two pipes A and B can fill a tank in 20 and 24 minutes. Resepctively. Pipe C can empty the tank in 10 minutes. Pipes A and B are opened for 5 minutes
Correct Answer - 55 minutes
2 Answers 1 views
10. Lymph differs from blood in possessing (1) More proteins and less waste products (2) Less proteins and more waste products (3) More proteins and more waste products (4) Less proteins and less waste products
(2) Less proteins and more waste products
2 Answers 1 views
Two different dice are thrown together. Find the probability that the numbers obtained (i) have a sum less than 7 (ii) have a product less than 16 (ii
Correct Answer - ` (i) 5/12 (ii) 25/36 (iii) 1/4`
2 Answers 8 views
A train travels a distance of 300km at constant speed. If the speed of the train is increased by 5 km/kr, the journey would have taken 2 hours less. F
Correct Answer - 25 km/hr
2 Answers 1 views