X = the number of humans and y = the number of horses.
x+y=74
2x+4y=196
Because the number of humans and horses together is 74, and the total number of legs (2 per every human, x, and 4 per every horse, y) is 196. Then, just use elimination to solve.
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So, now that you have y, you can plug it into the first equation to find x:
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So, x = 50 and y = 24, so there are 50 humans and 24 horses.
The correct answer is B.
The probability that x >17 will be found as follows:
the z-score is given by:
z=(17-15.2)/0.9=2
Thus
P(X>17)=1-P(x<17)=P-(z=2)
=1-0.9772
=0.0228
The first blank on the left side should be 0 I think
A kite is flying at an angle of elevation of 48 degrees