ANSWER
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Ratio of 8th graders to 7th graders = 3 : 2
Let the number of graders be 3x and 2x
Number of 8th graders = 18
So , 3x = 18
x = 18/3 = 6
Number of 7th graders = 2 × 6 = 12
Ratio of 6th graders to 7th graders = 5 : 4
Let the number of graders be 5a and 4a
Number of 7th graders = 12
So , 4a = 12
a = 12/4 = 3
Number of 6th graders = 5×3 = 15 ANS
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#BE BRAINLY
Answer:
48
Step-by-step explanation:
x/8+3=9
x/8=9-3
x/8=6
x=6*8
x=48
Answer:
C
Step-by-step explanation:
x = -1 and -7
(10x+5)4 = 30x + 3x + 6x +30
40x + 20 = 39x + 30
X = 10
perimeter of the square= 420
perimeter of the triangle= 420