self Maths Puzzle

A dance instructor conducts annual workshops in which he holds sessions for basic learners and trainers. In a particular year, 2000 people attended the workshop. 1500 participated as learners and 800 as trainers. How many participated as only trainers?
A) 200
B) 500
C) 800
D) 1500

Read Solution (Total 1)

n (A) = 1500
n (B) = 800
n (A union B) = 2000
n (A union B) = n(A) + n(B) - n(A intersection B)
2000 = 1500 + 800 - x
Hence, x = 300. i.e., 300 people were both trainers and learners.
Hence only trainers = 800 - 300 = 500. Answer.
11 years agoHelpfull: Yes(5) No(1)

self Other Question

When 242 is divided by a certain divisor the remainder obtained is 8. When 698 is divided by the same divisor the remainder obtained is 9. However, when the sum of the two numbers 242 and 698 is divided by the divisor, the remainder obtained is 4. What is the value of the divisor? A lady has some fine gloves and hats in her closet 14 blue,25 red and 45 yellow. The lights are out and it is totally dark. In spite of darkness, she can make out difference between a hat and glove. She takes out of the closet only if she is sure that it is a glove. How many gloves must she take out to make sure that she has a pair of each color?

A) 72
B)35
C)33
D)39