Solve the missing elements for each problem. use 3.14 for ~ | | . 1 ) s r t q radius: diameter: 4 inches circumference: area: 2 ) c b d a radius: diameter: 10 ft circumference: area: 3 ) r q s p radius: 18 yards diameter: circumference: area: 4 ) p o q n radius: diameter: 16 cm circumference: area: 5 ) e d f c radius: 19 mm diameter: circumference: area: 6 ) d c e b radius: 12 inches diameter: circumference: area: 7 ) j h k g radius: diameter: 28 ft circumference: area: 8 ) n m o l radius: 6 yards diameter: circumference: area: 9 ) h g j f radius: diameter: 18 cm circumference: area:

We know that
diameter=radius*2
radius=diameter/2
area of circle=pi*r²
length of circumference=2*pi*r
so

Part 1) 4 inches circumference
4=2*pi*r> r=4/(2*pi)> r=2/pi> r=0.64 in
diameter=2*0.64> 1.28 in
area=pi*0.64²> 1.29 in²

the answers Part 1) are
a) radius=0.64 in
b) diameter=1.28 in
c) area=1.29 in²

Part 2) 10 ft circumference
10=2*pi*r> r=10/(2*pi)> r=5/pi> 1.59 ft
diameter=2*1.59> 3.18 ft
area=pi*1.59²> 7.94 ft²

the answers Part 2) are
a) radius=1.59 ft
b) diameter=3.18 ft
c) area=7.94 ft²

Part 3) 18 yards diameter
radius=18/2> 9 yd
circumference=2*pi*9> 56.52 yd
area=pi*9²> 254.34 yd²

the answers part 3) are
radius=9 yd
circumference=56.52 yd
area=254.34 yd²

Part 4) 16 cm circumference
16=2*pi*r> r=16/(2*pi)> r=8/pi> 2.55 cm
diameter=2*2.55> 5.10 cm
area=pi*2.55²> 20.42 cm²

the answers Part 4) are
a) radius=2.55 cm
b) diameter=5.10 cm
c) area=20.42 cm²

Part 5) 19 mm diameter
radius=19/2> 9.5 mm
circumference=2*pi*9.5> 59.66 mm
area=pi*9.5²> 283.39 mm²

the answers part 5) are
radius=9.5 mm
circumference=59.66 mm
area=283.39 mm²

Part 6) 12 inches diameter
radius=12/2> 6 in
circumference=2*pi*6> 37.68 in
area=pi*6²> 113.04 in²

the answers part 6) are
radius=6 in
circumference=37.68 in
area=113.04 in²

Part 7) 28 ft circumference
28=2*pi*r> r=28/(2*pi)> r=14/pi> 4.46 ft
diameter=2*4.46> 8.92 ft
area=pi*4.46²> 62.46 ft²

the answers Part 7) are
a) radius=4.46 ft
b) diameter=8.92 ft
c) area=62.46 ft²

Part 8) 6 yards diameter
radius=6/2> 3 yd
circumference=2*pi*3> 18.84 yd
area=pi*3²> 28.26 yd²

the answers part 8) are
radius=3 yd
circumference=18.84 yd
area=28.26 yd²

Part 9) 18 cm circumference
18=2*pi*r> r=18/(2*pi)> r=9/pi> 2.87 cm
diameter=2*2.87> 5.74 cm
area=pi*2.87²> 25.86 cm²

the answers Part 9) are
a) radius=2.87 cm
b) diameter=5.74 cm
c) area=25.86 cm²