supplementary angles add up to 180°.
x = measure of such angle
x + 20 = measure of her sibling.
since "x" has 20 less than her sibling, then clearly her sibling has to have 20 more than "x".

The answer would
be 13/10
Answer:

Step-by-step explanation:
The circumference of a circle with radius
is given by
. The length of an arc is makes up part of this circumference, and is directly proportion to the central angle of the arc. Since there are 360 degrees in a circle, the length of an arc with central angle
is equal to
.
Formulas at a glance:
- Circumference of a circle with radius
:
- Length of an arc with central angle
: 
<u>Question 1:</u>
The radius of the circle is 12 m. Therefore, the circumference is:
The measure of the central angle of the bolded arc is 270 degrees. Therefore, the measure of the bolded arc is equal to:

<u>Question 2:</u>
In the circle shown, the radius is marked as 2 miles. Substituting
into our circumference formula, we get:

The measure of the central angle of the bolded arc is 135 degrees. Its length must then be:
