Mathematics
The mean of the following frequency distribution is 50, but the frequencies f1 and f2 in class 20-40 and 60-80 respectively are not known. Find these frequencies.
| Class | Frequencies |
|---|---|
| 0-20 | 17 |
| 20-40 | f1 |
| 40-60 | 32 |
| 60-80 | f2 |
| 80-100 | 19 |
Given that the sum of frequencies is 120.
Related Questions
A card is drawn at random from a well-shuffled deck of 52 playing cards. Find the probability that it is :
(i) an ace
(ii) a jack of hearts
(iii) a three of clubs or a six of diamonds
(iv) a heart
(v) any suit except heart
(vi) a ten or a spade
(vii) neither a four nor a club
(viii) a picture card
(ix) a spade or a picture card.
Solve for x ∈ W, 0° ≤ x ≤ 90°.
(i) 3 tan2 2x = 1
(ii) tan2 x = 3(sec x - 1)