Answer:
A pack of pencil' price=$8
Price went up=$12
increasing percentage = change/original x100
= (12 -8)/8 x100
=4/8 x100
=50%
Answer:

Step-by-step explanation:
We are given that The monthly charge for a waste collection service is 1830 dollars for 100 kg of waste
So, 
We are also given that The monthly charge for a waste collection service is 2460 dollars for 135 kg of waste.
So, 
We are supposed to find a linear model for the cost, C, of waste collection as a function of the number of kilograms, w.
So, we will use two point slope form :
Formula : 
Substitute the values





y denotes the cost
x denotes the weight
So, Replace y with C and x with w

So, a linear model for the cost, C, of waste collection as a function of the number of kilograms, w is 
Answer:
30 is the least common factor or lcm
Step-by-step explanation:
when adding fractions you always have to find the lcm
One option for the final answer is 30 and 22...
I think I would use the second answer that you provided
The probability is 4:20
It is correct because there are 20 students and there could be 4 guesses