14 bags of fertilizer are needed
Solution:
Given that You need to buy fertilizer for a circular flower bed with a diameter
of 13 feet
Diameter = 13 feet
[tex]radius = \frac{diameter}{2}[/tex]
[tex]radius = \frac{13}{2} = 6.5[/tex]
Therefore radius of circular flower bed is 6.5 feet
Area of circle is given as:
[tex]\text{ area of circle } = \pi r^2[/tex]
Substitute r = 6.5
[tex]\text{ area of circle } = 3.14 \times 6.5^2 = 132.665[/tex]
Given that one bag will fertilize 10 square feet
1 bag = 10 square feet
Then number of bags needed are:
[tex]\rightarrow \frac{132.665}{10} = 13.2665[/tex]
Thus approximately 14 bags of fertilizer are needed
