I would would say 7.
Mom + Dad + daughter + daughter + daughter + daughter + plus one brother = 7
Since they are all sisters and it says each one has one brother I think that would mean 7. That's just my comprehension of the question, though I may 100% wrong.
John's hourly rate is 1/8 of the room per hour.
Rick's hourly rate is 1/2 of the room per hour.
Molli's hourly rate would be 3/8 of the room per hour.
It takes Molli 2 2/3 hours to paint the room alone.
Explanation
Since John paints the entire room (100%=1) in 8 hours, he would paint 1/8 of the room in 1 hour.
Since Rick paints the entire room (100%=1) in 2 hours, he would paint 1/2 of it in 2 hour.
We do not yet know Molli's rate, so we will call it x.
We know that 1/8+1/2+x = 1 hour.
We will use 8 as a common denominator:
1/8+4/8+8x/8 = 1
Adding the numerators,
(1+4+8x)/8 = 1
Multiply both sides by 8:
1+4+8x = 8
Add like terms:
5+8x = 8
Subtract 5 from both sides:
5+8x-5=8-5
8x=3
Divide both sides by 8:
8x/8 = 3/8
x = 3/8
Molli's rate is 3/8.
Since she can paint 3/8 of the room in 1 hour, we can set up the equation
3/8x = 1
Divide both sides by 3/8:
3/8x ÷ 3/8 = 1 ÷ 3/8
x = 1/1 ÷ 3/8 = 1/1 × 8/3 = 8/3
x = 2 2/3
This is the amount of time it takes Molli to paint the entire room.
See the attached diagram, it has all the information you need.
(a) If the green radii are all 1, then the orange diameters are all 2 + √2, so that the orange radii are (2 + √2)/2 = 1 + √2/2.
This is because we can join the radii of two adjacent green circles to form the sides of a square with side length equal to twice the radius - i.e. the diameter - of the green circles. The diagonal of any square occurs in a ratio to the side length of √2 to 1. Then we get the diameter of an orange circle by summing this diagonal length and two green radii, and hence the radius by dividing this by 2.
(b) We get the blue diameter in the same way. It has length (2 + √2) (1 + √2/2) = 3 + 2√2, so that the blue radius is (3 + 2√2)/2 = 3/2 + √2.
Answer:
B
Step-by-step explanation:
that seems like the best option to me