1. First, put the range in order and then divide the set into quarters. In this case, quartiles are between numbers. <span>83, 85, 89, l 91, 95, 104, l 112, 118, 118, l 125, 134, 138 Q</span>₁ = (89 + 91)/2 = 90 Q₂ = (104 + 112)/2 =108 Q₃ = (118 + 125)/2 = 121.5 Interquartile range (IQR) = Q₃ - Q₁ = 121.5 - 90 IQR = 31.5 2. To find the standard deviation follow the simple steps. Formula in finding the standard deviation: (see attached file) Step 1. Work out the simple average of the numbers (mean) <span><span><u>212 + 249 + 212 + 248 + 239 + 212 + 216 + 234 + 248</u> </span> 9 = <span><u>2070</u> </span> 9 mean (</span>μ) = 230
Step 3. Add all the squared results and get the mean. <span><u>2274</u> </span> 9 Variance = 252.6666667 Step 4. Get the square root of the variance. √252.6666667 = 15.89549202
Coordinates of the midpoint of AC: M ( (-6-2) / 2) , ( 7-9 ) /2 ) = ( -4, -1 ) d ( BM ) = √ ( 4 + 4 )² + ( -1+ 1 )² d ( BM ) = √ 8 ² =√ 64 = 8 The length of the median from angle B is 8.