Answer:
4.  300 girls
5.  38 fish
6.  36 points
7.  115 marbles
8.  18 gray colored cars
Step-by-step explanation:
4.
<u>  30 </u> = <u> 500 </u>
 18G       x
30x = 500 (18)
x = 300 girls
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5.
<u>2.5 mils </u>  =  <u> 8 miles </u>  
 12 fish              x
2.5x = 8 (12)
x = 96/2.5
x = 38 fish
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6.
<u>  8 mins </u>   =   <u> 21 mins</u>
14 points            x
8x = 21 (14)
x = 294/8
x = 36 points
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7.
<u>32 marbles  </u> =    <u>         x         </u>
  5 inches             18 inches
5x = 32 (18)
x = 576 / 5
x = 115 marbles
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8.
<u>140 cars </u> =  <u> 15 cars  </u>
     x              2 gray
15x = 140 (2)
x = 280 / 15
x = 18 gray colored cars
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