70 POINTS!! AND BRAINLIEST HELPPPPP!!!

Answer:
4. 300 girls
5. 38 fish
6. 36 points
7. 115 marbles
8. 18 gray colored cars
Step-by-step explanation:
4.
30 = 500
18G x
30x = 500 (18)
x = 300 girls
---------------------------------
5.
2.5 mils = 8 miles
12 fish x
2.5x = 8 (12)
x = 96/2.5
x = 38 fish
---------------------------------
6.
8 mins = 21 mins
14 points x
8x = 21 (14)
x = 294/8
x = 36 points
---------------------------------
7.
32 marbles = x
5 inches 18 inches
5x = 32 (18)
x = 576 / 5
x = 115 marbles
---------------------------------
8.
140 cars = 15 cars
x 2 gray
15x = 140 (2)
x = 280 / 15
x = 18 gray colored cars
---------------------------------
Answer:
Step-by-step explanation:
Let the unknown values be x
1.
30 class mates = 1 class room
18 girls in 1 classroom
18 girls in 30 classmates
x girls in 5000 class mates
[tex]18\:girls= 30\:students\\x\:girls = 5000\:students\\\\Cross\:Multiply\\\\30x = 90000\\\\Divide\:both\:sides\:by\:30\\\frac{30x}{30} = \frac{90000}{30}\\ \\x = 3000\\= 3000 girls[/tex]
2.
[tex]2.5\:miles = 12 \:fishes\\8\:miles = x\:fishes\\\\Cross\:Multiply\\2.5x = 96\\\\Divide\:both\:sides\:of\:the\:equation\:by\:2.5\\\\\frac{2.5x}{2.5}=\frac{96}{2.5}\\ \\x = 38.4\\Approximately \: =38\:fishes[/tex]
3.
[tex]8\:minutes = 14\: points\\21 \:minutes = x \:points\\\\Cross\:Multiply\\8x = 294\\\\\mathrm{Divide\:both\:sides\:by\:}8\\\frac{8x}{8}=\frac{294}{8}\\\\Simplify\\x=\frac{147}{4}\\\\x = 36.75\\\\Approximately\:= 37\:points[/tex]
4.
[tex]32\:marbles = 5\:inches\\x\:marbles = 18\:inches\\\\Cross\:Multiply\\5x = 576\\\\\mathrm{Divide\:both\:sides\:by\:}5\\\frac{5x}{5}=\frac{576}{5}\\\\x=\frac{576}{5}\\\\x =115.2\\= 115=\:marbles[/tex]
5.
[tex]2 \: gray\:colour= 15\:cars\\x\:gray= 140\:cars\\\\Cross\:Multiply\\\\15x = 280\\\\\mathrm{Divide\:both\:sides\:by\:}15\\\frac{15x}{15}=\frac{280}{15}\\\\Simplify\\x=\frac{56}{3}\\\\x =18.666\\Approximately ;\\19[/tex]