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# A cell phone company charges a monthly fee of $20 for the first 1600 text messages and 40 cents for each additional text message. MiriamÂs 0 396 1 A cell phone company charges a monthly fee of$20 for the first 1600 text messages and 40 cents for each additional text message. MiriamÂs bill for text messages for the month of June is $42.80. How many text messages did she send that month? Guest May 22, 2017 #1 +2263 +1 Mariama sent 1657 text messages during June. Okay, the situation you have mentioned above can be represented as a linear expression; Let t=amount of text messages above 1600. $$20+0.4t$$ In the expression above you pay$20 for every text message until Mariama surpasses 1600 texts. Once that happens, Mariama is charged 40 cents for every additional text message. Set this expression equal to the bill, \$42.80, and solve:

$$20+0.4t=42.80$$

For ease of calculation, I will get rid of that decimal by converting to a fraction:

$$20+\frac{4}{10}t=42.80$$     Multiply by 10 on each side to get rid of the fraction, which eases solving significantly.

$$200+4t=428$$     Subtract 200 on both sides.

$$4t=228$$     Divide by 4 to isolate t, the number of texts.

$$t=57$$

Wait! We aren't done yet! 57 is the number of texts made over the allotted 1600. Add 57 to 1600 and then you are done.

$$1600+57=1657$$ texts made during the month of June.

TheXSquaredFactor  May 22, 2017