pls help me .... pls
Answers
Answer:
35 : 55 (7 :11 in simplified form) is the ratio of boys to girls in whole school.
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Explanation:
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2 : 3 = 2x : 3x ( as ratios are in simplified form). So there are 5x (2x+3x) students in class 8 in total
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3 : 7 = 3y :7y. So there are 10y students in class 9 in total
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7 : 8 = 7z : 8z. So there are 15z students in class 10 in total
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So, 5x = 10y = 15z (as you said they have same no. of students in every class)
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The LCM of 5,10,15 is 30.
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So, there are 30 students in each class
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Based on this information find the values of x,y,z to find no. of girls and boys separately.
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For class 8 :
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2x + 3x = 5x = 30
x= 6,
no. of boys = 2x = 2*6 = 12
no. of girls = 3x = 3*6 = 18
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For class 9 :
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3y + 7y = 10y = 30
x = 3
no. of boys = 3y = 3*3 = 9
no. of girls = 7y = 7*3 = 21
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For class 10 :
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7z + 8z = 15z = 30
z = 2
no. of boys = 7z = 7*2 = 14
no. of girls = 8z = 8*2 = 16
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Total no. of boys in all classes = 12+9+14 = 35
Total no. of girls in all classes = 18+21+16 = 55
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total boys : total girls = 35 : 55 = 7 : 11
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HOPE IT HELPS
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PLEASE MARK ME BRAINLIEST
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