I think it's 19.0
because i got one & it is less than 4 so i let it rest
X-27=-1
x represents unknown number
7+3 = 10 total marbles
1st pick = 7/10 for a red one
2nd pick = 6/9 reduces to 2/3 for a red one
3rd pick = 3/8 for a white one
7/10 x 2/3 =14/30 reduces to 7/15
7/15 x 3/8 = 21/120 reduces to 7/40
probability = 7/40
7)3,916 8)3,521 9)21,285 10)54,16.
11) 4,710 12) 2,091 13) 17,128 14) 55,713
Answer:
180-n_c
Step-by-step explanation:
Given that the ratio of children to adults is 2:1.
Let
and
be the number of children and adults in the school carnival.
So, 

Given that the total number of peoples in the carnival =180
So, 

Now, from equations (i) and (ii), we have

Hence, the number of children in attendance is 120.