Step-by-step explanation:
m< AOC = 90°
m< AOB +m<BOC = 90°
6x-12+3x +30 = 90°
9x +18° = 90°
9x = 90- 18° = 72°
x = 8°
m<AOB =6(8)-12 = 48-12 = 36°
Use dimensional analysis:
Since we multiplied a numerator and a denominator by centimeters, we are only left with meters.
This answer is already is three significant figures by default.
<u>8th Grade: </u>90 x 0.80 = 72
<u>7th Grade:</u> 80 x 0.75 = 60
Conclusion: 8th Graders like pop music more because 72 out of the 90 in 8th grade Dave surveyed enjoy it, compared to the 60 out of 80 in 7th grade that enjoyed it.
