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3 years ago

Mark has $6.35 in quarters and dimes. He has 5 more than twice as many dimes as quarters. How many quarters does Mark have?

Mathematics

1 answer:

sukhopar [10]3 years ago

8 0

Answer:

Mark has 12 quarters

Step-by-step explanation:

I did all of it, nickles, dimes, and of course, quarters..

So, Let +n+ = the number of nickels he has

Let +d+ = the number of dimes he has

Let +q+ = the number of quarters he has

given:

(1) +q+=+2n+

(2) +d+=+n+%2B+3+

(3) +5n+%2B+10d+%2B+25q+=+420+

( the units for this equation is cents , for instance,

$4.20 is 420 cents

All you have to do is substitute (1) and (2) into (3)

so that the only variable is +n+, then solve

(3) +5n+%2B+10%2A%28+n+%2B+3+%29+%2B+25%2A%282n%29+=+420+

(3) +5n+%2B+10n+%2B+30+%2B+50n+=+420+

(3) +65n+%2B+30+=+420+

Subtract +30+ from both sides

(3) +65n+=+390+

(3) +n+=+6+

And since

(2) +d+=+n+%2B+3+

(2) +d+=+6+%2B+3+

(2) +d+=+9+

Also, since

(1) +q+=+2n+

(1) +q+=+2%2A6+

(1) +q+=+12+

: Mark has 6 nickels, 9 dimes, and 12 quarters

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Let the total number of leaves on the tree be x.

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$\color{plum} = \tt 48 \: green \: \: leaves$

Thus, the total number of green leaves on the tree = 48

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