Given:
5 students are able to share 20 crayons.

For 30 students,

Answer: There are 120 crayons are needed for 30 students.
Deci- means 1/10 or .1 of a unit.
Probably y = 8x. 56 = 8(7), so that works. Without more data, I couldn't say if it could be something else, so that's what I go with.
Answer:
Step-by-step explanation:
1) 30 : 100 = x : 299
x = (30 x 299)/100
x = 89,70 $
2) 299 - 89,70 = 209,30 $
3) 5 : 100 = x : 209,30
x = 10,465 $
209,30 + 10,465 = 219,77 $