Question
Two hats are picked at random, what is the probability
that all hats are of green colour? A box contains 6 red, 4 blue, 2 green and 4 yellow hats.Solution
Total number of hats = 6 + 4 + 2 + 4 = 16 Let S be the sample space. Then, n(S) = number of ways of drawing 2 hats out of 16 = ¹⁶C_₂ = (16 × 15)/( 2 × 1) = 120 Let E= event of drawing all the hats are of green colour n(E) = ²C_₂ = 1 ∴ P (E) = (n(E))/(n(S)) = 1/120
The cost of a piece of diamond varies with the square of its weight. A diamond of Rs.6,084 value is cut into 3 pieces whose weights are in the ratio 3: ...
'A' varies directly as 'B'. If at 'A' = 25, value of 'B' is 40, then find the value of 'A' at 'B' = 96.
The earnings of two individuals, P and Q, are in the ratio of 4:7. After an increase of 30% in Q’s earnings, his total earnings amount to Rs. 27,300. ...
Two numbers are in the ratio 5 ∶ 9. If each number is decreased by 8, the ratio becomes 1 ∶ 3. The numbers are:
The average height of three boys is 170 cm. If their heights are in the ratio 6:4:7, what is the height of the tallest boy?
Find the third proportional to 12 and 42?
A, B and C entered into a partnership by investing in the ratio of 7:4:5. At the end of the year, the total profit is in the ratio of 21:4:10. Find the ...
A grandmother distributed a total of 480 gold coins between her two sons in the ratio of (x + 1) to (x – 1). The difference in the number of coins rec...
A starts a business with Rs. 5650. After 8 months, B joins with A as his partner. After one year the profit is divided in the ratio 5:8. What is B&rsquo...
The ratio between two numbers is 1:2. If each number is increased by 8, the ratio between then become 5:6, find the difference between numbers.