The cost of 5 boxes of envelopes and 5 boxes of notebook paper is $25.95. Two boxes of envelopes and 6 boxes of notebook paper is $22.38. How much does 1 box of envelopes cost?

Answer 1

You are given two scenarios for a combination of envelopes ✉️ and notebooks 📓. The first thing that I would do is set up a math equation for each scenario. Assign the letter e for envelopes and n for notebooks. These letters represent the cost for each item. So, the first statement says 5e+5n=25.95, and the second statement says 2e+6n=22.38

Now, we can find the cost of one ☝️ envelope (e), by solving these two equations. My next step would be to isolate e in one of the equations: e=(-5n+25.95)/5. Then, substitute the e in the second equation with the expression found: 2((-5n+25.95)/5)+6n=22.38

Once the equation with only n is simplified by multiplying and combining terms with n, we can find the cost of one notebook 📓 (n=3). Afterwards, we substitute the cost of one notebook to find the cost of one box envelopes ✉️ (e=2.19) . The value of e is the answer we are looking for.

Note: If the n was isolated first then we would find the value of e right away (A faster approach).