Word Marth Challenge
Out of 100 collectors, 70 collect coins, 75 collect badges, 80 collect match box labels and 85 collect stamps.
How many collectors are involved in all 4 types of hobbies ?.
Answer:
Let collectors of all 4 types be x
then: 100 = (70- x) + (75 - x) + (80 - x) + (85 - x) + x
100 = 310 - 4x +x
3x = 210
[x = 70
70 collectors are involved in all 4 types of hobbies.
