Problem: isabella is buying art supplies the table shows the prices for the items she buy |table : glass beads $0.28 per ounce $0.95 paint brush 0.75$ poster board jar of paint $0.99. she spends 2.25 on poster boards how many does she buys part b isabella spends $4.87 on paint brushes and paint how many of each item does she buy explain how u found it answer. can’t figure it out need !

the complete question in the attached figure

Part A

we know

price poster boards----------- > $0.75

let

p------------- > number of poster boards

q------------- > money spends on poster boards----------> $2.25

q=p*0.75---------> p=q/0.75=2.25/0.75=3

the answer part A is 3

Part B

Let 

x-------------- >number of paint brushes------------ > $0.95

y-------------- >number of jar of paint ------------ > $0.99

we know

0.95x+0.99y=4.87

using a graph tool

see the attached figure

the solution is the line shown in the graph

answer: expected value of x = 1.0

step-by-step explanation:

p(x=0) = 0.25

p(x=1) = 0.50

p(x=2) = 0.25

expected value for x = 0×0.25 + 1×0.5 + 2×0.25 = 1.0