Stoopid, its 200 centimeters
4/52 because 4 of each number and 52 total.
Convert to base 10
2×3² + 0×3¹ + 1×3^0 = 18 + 0 +1 = 19 base 10
so convert 19 to base 8
19 base 10 = 23 base 8
D is your answer
He worked 3 8-hour days.
Let x be the number of 8 hour days. Then 10-x is the number of 6 hour days.
8x + 6(10-x) = 66
Using the distributive property,
8x + 6*10 - 6*x = 66
8x + 60 - 6x = 66
Combining like terms:
2x + 60 = 66
Subtract 60 from both sides:
2x + 60 - 60 = 66 - 60
2x = 6
Divide both sides by 2:
2x/2 = 6/2
x = 3
#8 is C
#9 is D
#10 is C
#11 is A