Answer: 2.87 hours
Step-by-step explanation:
There may be a typo in the question because 55 hours in a day is not logical so you must have meant 5.5 hours.
In that case, the hours he will require on the third day would require the distance left to calculate. Get this distance from the first 2 days.
Day 1 distance travelled = Time * Speed
= 5.5 * 66
= 363 miles
Day 2 distance travelled = Time * Speed
= 5.5 * 58
= 319 miles
Total distance remaining
:= 840 - 363 - 319
= 158 miles
Travelling at 55 miles per hour, the time to be taken is:
= Distance remaining / Speed
= 158 / 55
= 2.87 miles per hour
Answer: The answer is (D) 
Step-by-step explanation: Given that there is a rectangle, where length of the rectangle is given by

and width of the rectangle is given by

We are to find the perimeter of the rectangle. To do so, we need to add two times length with two times breadth of the rectangle.
Therefore, perimeter is given by

Thus, the correct option is (D).
Answer:
0.36
Step-by-step explanation:
Percentage of boys = 60%
Percentage of girls = 100 - 60 = 40%
Percentage of boys that arrive by car
= 20% of 60%
= 0.2 x 60 = 12%
Percentage of girls that arrive by car
= 60% of 40%
= 0.6 x 40
= 24%
Total Percentage of children arrive by car
= 12 + 24
= 36%
P(Arrive by car)
= 36%
= 0.36