Answer:

Step-by-step explanation:
We have,
Radius of the circle is 12 cm
Arc length, l = 21 cm
It is required to find the central angle of the circle. The formula for the length of an arc of a circle is :

is central angle

So, the angle at the centre of the circle is
.
Answer:
C (circumference) =2×π×r
we've got a 30-60-90 triangle
which means 9=d√3, d=5.19 exact inches
or ≈5.20 inches
d=2r, r=5.20÷2≈2.60 inches
C=2×3.14×2.60≈16.328
5,000 - bag of fertilizer
500 - Mike’s lawn
3/4 - applied fertilizer
4 - frequency in 1 year
(500 x 3/4 )x 4
(1500 / 4 ) x 4
1500 sqm / yr
5,000 sqm / 1500sqm/yr
3.33 yr
He will be able to fertilize it in 3 full years
Answer:
Class Boundary = 1 between the sixth and seventh classes.
Step-by-step explanation:
Lengths (mm) Frequency
1. 140 - 143 1
2. 144 - 147 16
3. 148 - 151 71
4. 152 - 155 108
5. 156 - 159 83
6. 160 - 163 18
7. 164 - 167 3
The class boundary between two classes is the numerical value between the starting value of the higher class, which is 164 for the 7th class in this case, and the ending value of the class of the lower class, which is 163 for the 6th class in this case.
Therefore the class boundary between the sixth and seventh classes
= 164 - 163 = 1
Therefore Class Boundary = 1.
It can be seen that class boundary for the frequency distribution is 1.
If we take the difference between the lower limits of one class and the lower limit of the next class then we will get the class width value.
Therefore, Class width,
w = lower limit of second class - lower limit of first class
= 144 - 140
= 4