Answer: Choice C
The first inequality is [tex]124+121+x \ge 400[/tex]
The second inequality is [tex]x \ge 155[/tex]
Replace x with whatever letter your teacher is using
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Let x be the number of cans collected on week 3
Add this to the previous totals (for weeks 1 and 2) to get 124 + 121 + x. I'm going to leave this as is and not simplify. This is so the answer matches up. This total must be greater than or equal to 400, meaning 124+121+x can be 400 or larger.
124+121+x >= 400
245+x >= 400 .... combine like terms
x >= 400-245 .... subtract 245 from both sides
x >= 155
So you need to collect at least 155 cans for the third week so that you'll have at least 400 cans total.
