4th from the top: 1/2base x height
1/10 = .1, and 3/33 = .0909090... it is equivalent if you estimate.
<span>0.05 arc-second = 1 degree/72000 = (pi
radians)/(180*72000) = 2.424 x 10^(-7) radians</span>
<span>The distance is roughly: </span>
<span>R*(theta) = (600 light-years)*2.424 x 10^(-7) = 0.00014544 light-years = 1.275
light-hours = (3600 seconds)*(3 x 10^8 m/s)*(1.275) = 1.38 x 10^12 meters.</span>
Answer: $56.50
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(instead of dividing each of them individually and them subtracting them one by one, combine them together as a fraction first and then subtract)
80 - (68/5 + 51/2 + 22/5)
= 80 - (136/10 + 255/10 + 44/10)
= 80 - (435/10)
= 80 - 43.5
= 56.5
He saved $56.50 on that