Phillip bought 12 used cds and dvds. cds cost $2 each, and dvds cost $3 each. he spent $31, not including tax. how many dvds did phillip buy? 10 7 5 2

He spent $31, not including tax, Philips buys 7 DVDs .

Given that,

Total no. of CDs and DVDs is = 12

CDs cost each = $2

And DVDs cost $3 each.

He spent $31, not including tax.

We have to find

How many DVDs did Phillip buy.

According to the question,

By using the elimination method,

If he buys 10 DVD's = (10).(3) + tax = $30 , he would have spent $34 (including CD's) with,

5 DVD's he spends = (5).($3) + (5).($2) + tax = $29 (including CD's) with

2 DVD's he spends = (2).($3) + (2).($2) + tax =  $10 (including CD's)

So, with 7 DVD's = (7).($3) = 21 that is $21 and with 5 CD's = (5).(2) = 10 that is $10 and $21 + $10 is $31.

Hence, Philips required to buy 7 DVDs .

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