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
He needs to save $150 each of the last two months.
Step 1 : Simplify both sides
-5(6a+21)=-15
(-5)(6a)+(-5)(21)=-15
-30a-105=-15
Step 2 : Add 105 to both sides
-30a-105+105=-15+105
-30a=90
Step 3 : Divide both sides by -30
-30a=90
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-30 -30
a = -3
Answer:
Given that a beetle has the pattern, 0.098 is the probability that it belongs to the rare subspecies
Step-by-step explanation:
Probability of having a pattern in rare subspecies 
Percentage of rare subspecies = 1 % = 0.01
Probability of a beetle with pattern belonging to rare subspecies is
Answer:
h = 197
Step-by-step explanation:
add 14 to each side, and h = 197
