Markers are on sale for $4.50 for black, $3.25 for red, and $1.98 for green. he spends a total of $284.24. if he buys a certain number of black markers, twice the number of black markers in red, and three times the number of black markers in green, how many of each color did this person purchase?

Let x be number of black markers

4.5x + 2x3.25x + 3x1.98x = 284.24
16.94x = 284.24
x = 16.78 = 17

The person bought 17 black pens, 34 red and 51 green

The simplified form of this expression (- + ) + (4 − − 1) is 3 − 1.

Step-by-step explanation:

First step for simplifying the equation is to put all the variables with same degree of power at one place:So,                         - + 4 + - - 1                                                                                            

                                   =   3 − 1.

We performed the addition and subtraction of the variable's coefficient with same order of power i.e (-1+4) +(1-1) -1.Finally the equation in the questions is reduced to simpler form as     3-1. The easy method to check is, assign any number to value of (say =2) in question. Now the option that gives the same value as question is our answer.