168cm2
Let r cm be the radius of the balloon, then
<span>2pi(r)=23=>r=23/(2pi) </span>
<span>The surface area= </span>
<span>4pi(r^2)= </span>
<span>4pi[23/2pi)]^2= </span>
<span>(23^2)/pi=168.386 cm^2 </span>
<span>approximately.</span>
Using the Sine Rule:-
20 /sin 45 = BC / sin 30
BC = 20 sin 30 / sin45
= 20 * 1/2 / 1 / sqrt2
= 20 * 1/2 * sqrt2
= 10 sqrt2 answer
<span>The mean of a set of data is 148.87 and its standard deviation is 68.29. Find the z score for a value of 490.19
the z-score is given by:
z=(x-</span>μ<span>)/</span>σ
plugging in the values in the expression we get:
z=(490.19-149.87)/68.29
z=340.32/68.29
z=4.9835
Well, the first one is 2/40=1/20. The 2nd one is 1/39. You multiply these to get 1/780.