Use Square of Sum: (a + b)^2 = a^2 + 2ab + b^2
b^2 + 2b * 12 + 12^2
Simplify 12^2 to 144
b^2 + 2b * 12 + 144
Simplify 2b * 12 to 24b
b^2 + 24b + 144
If you imagine a clock, the minute hand would've moved for 25% or 1/4 of the clock. So we need to find 1/4 of a circle in degrees
Because a circle is 360 degrees, we can do 1/4*360 which will get us 90°
Hope this helps
Answer:
the probability that a randomly selected duck weighs more than 1.8 kg is 5-10%
2 71
3 86
4 101
6 131
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