Answer:
see explanation
Step-by-step explanation:
Given that M is directly proportional to r³ then the equation relating them is
M = kr³ ← k is the constant of proportion
To find k use the condition when r = 4, M = 160, thus
160 = k × 4³ = 64k ( divide both sides by 64 )
2.5 = k
M = 2.5r³ ← equation of variation
(a)
When r = 2, then
M = 2.5 × 2³ = 2.5 × 8 = 20
(b)
When M = 540, then
540 = 2.5r³ ( divide both sides by 2.5 )_
216 = r³ ( take the cube root of both sides )
r =
= 6
Answer:
Final exam, Homework, Projects, quizzes
Step-by-step explanation:
15% is the lowest, 1/5 is 20% so that's next, 25% is the next largest, and 0.4 is 40%
Circumference of the outer circle = 2πr = 2π(6) = 12π
circumference of the outer arc = 120/360 x 12π = 12.57cm
circumference of the inner circle = 2πr = 2π(5) = 10π
circumference of the inner arc = 120/360 x 10π = 10.47 cm
Difference in length = 12.57 - 10.47 = 2.1cm (1 d.p.)
Answer: 2.1cm
You just need to make a completebox and to complete boxes by adding what you know together. By doing this you can get 1120