Basically
Circumference = 2 * pie * radius
To get the radius u need to measure the circles distance. For example I measured a circular mirror and the distance was 10cm. This is the diameter. To get the radius I’ll divide by 2 because the radius is from the centre of the circle to the edge. So, 10 divided by 2 = 5cm. The radius is 5cm. Now,
Circumference = 2 * pie * r
r = 5. Pie = 3.14
Circumference = 2 * 3.14 * 5
= The answer
****pie is always 3.14
I hope you understood
Answer:
Step-by-step explanation:
If the new fraction is 8/12 I will show how to find it.
Let's say the original denominator is x, then the numerator is x-4, so we have (x-4)/x.
Then it says f we add 4 to both, so now we have x/(x+4) this equals 8/12. Now, keep in mind -4 cannot be an answer because it would make x/(x+4) be divided by 0 which wouldn't exist.
Now we just use algebra.
x/(x+4) = 8/12
12x = 8(x+4)
12x = 8x + 32
4x = 32
x = 8
So the original fraction (x-4)/x = (8-4)/8 = 4/8
The answer is C. I need a total of 20 characters so heres a smiley face:)
Let's call your speed "a"
her walking speed is then "2a"
and her friend's scooter speed is 10 a
let's also call the distance you need to walk "d"
so the time (t)you need is:
d/t=a
t=d/a
and her time is:
t=

(half a distance with the speed of 2a and half a distance (d/2) with the distance of 10 a
now we count (we know that her time is 30 minutes)
30=

//multiply by 20a
600a=

600a=6d/divide by 6
100a=d
Now, in order to calculate your time we need to calculate:
t=d/a
but we know how much is d now!
t=

=100
which means that you need 100 minutes, or 1 h 40 minutes!!!