Answer:
circumference of the cake board = 109.9 cm
Step-by-step explanation:
diameter of cake = 30cm
diameter of cake board = 5cm longer than 30cm = 5 + 30 = 35cm
radius cake board = diameter ÷ 2 = 35 ÷ 2 = 17.5 cm
radius of cake board = 17.5 cm
circumference of a circle = 2 × π × r (where π = 3.14)
circumference of a circle = 2 × 3.14 × 17.5 = 109.9 cm
Therefore the circumference of the cake board = 109.9 cm
This one is easy all you have to do is subtract the 2.25 by the 15 to get 12.75.
A way you can show work is just not use the commas then subtract then put the commas in when you're done. And, if the bigger number isn't as big or has as many numbers behind the decimal as the first one, add a zero at the end.
First term, a
1
=4
Second term, a
2
=8
Common difference, d=a
2
=a
1
d=8−4=4
∴ The common difference is 4