8. 70.5* 10. 30* 12. 5.1*
120 tennis racquets were sold for $ 18 each
<em><u>Solution:</u></em>
Let x = number that sell for $18 each
Then, 200 - x = number that sell for $33 each
<em><u>The total receipts form these sales were 4800 dollars</u></em>
Thus we frame a equation as:
number that sell for $18 each x 18 + number that sell for $33 each x 33 = 4800
Thus 120 tennis racquets were sold for $ 18 each
4. 3(y + 4y) this is distributive property! Hope it helps. Btw can you please check out a question on my page? thanks!! <span />
With amounts measured in gallons, let
x = amount of 65% antifreeze
y = amount of 90% antifreeze
1 gal of the 65% brand contains 0.65 gal of pure antifreeze; x gal would contain 0.65x gal. Similarly, y gal of the 90% brand contains 0.90y gal of pure antifreeze.
To obtain 120 gal of 80% antifreeze solution (which contains 0.80•120 = 96 gal of pure antifreeze), we must have
x + y = 120 … … … … … [total volume of antifreeze solution]
0.65x + 0.90y = 96 … [total volume of pure antifreeze]
Solve the first equation for y :
y = 120 - x
Substitute this into the second equation and solve for x :
0.65x + 0.90 (120 - x) = 96
0.65x + 108 - 0.90x = 96
0.25x = 12
x = 48
Solve for y :
y = 120 - 48
y = 72