12 sessions.
EXPLANATION:
each session is 1 3/4 hours.
We need enough sessions for 21 hours.
the equation is 1 3/4 x f = 21
using the multiplication property of equality, we can do 21 divided by 1 3/4
The answer is 12 sessions.
Hope it helps!
<u>Given</u>:
The satang coin from Thailand has a radius of about 7 mm.
We need to determine the diameter and circumference of the coin.
<u>Diameter of the coin:</u>
The diameter of the coin can be determined by multiply the radius by 2.
Thus, we have;

Substituting r = 7, we get;


Thus, the diameter of the coin is 14 mm.
<u>Circumference of the coin:</u>
The circumference of the coin can be determined using the formula,

Substituting
and
, we get;


Thus, the approximate value of the circumference of the coin is 43.96 mm
Hopefully this helps, I have tried to write out all reasoning
A.

b and c.
add 5 to both sides:

subtract 3n from both sides: