The angle RSV would be 42°
Answer:
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We want the integral of the standard normal from -z to z to be 0.85. Let's look at some standard normal tables and pick the right one.
It's easy to find the Erf one, which is the integral of the unit normal from 0 to z. That will be exactly half of the integral from -z to z. So we look for the z value corresponding to a probability of 0.425 in that table and find
z = 1.44
Answer: 1.44
[figure from Wikipedia]
Here how it goes, 12 boys to 8 girls is 3:2 in ratio form but since u adding 2 more girls then 8 girls + 2 girls = 10 girls so now its 12 boys + 10 girls so your answer in final would be 6:5.