Growth and decay Quiz
10 questions · easy to harder · Differential Equations · score and step-by-step answers
How it works
- 10 questions, about 30 minutes (a timer counts down; you can hide it). Solve it right here: no sign-up.
- 5 questions have choices. For the others you type the answer: a number like 4, −2, 7/2 or 3.5, or for example x = 4, x = 2 or x = −3, (3, 5), 2x + 1. Use ^ for powers (x^2) and sqrt for √. Any form with the same value counts (7/2 = 3.5).
- One question at a time: Back, Next, Mark for review and the question list at the bottom. A calculator is on the screen.
- At the end: your percent and grade, every question right or wrong, why a wrong choice is wrong, and its step-by-step solution. Then practise the lesson with new questions.
Your answers and results are kept in this browser only, so you can close the page and come back.
1 Question 1
dP/dt = 0.03P, P(0) = 500, find P(10)- A) 674.93
- B) 500
- C) 6749.3
- D) 650
2 Question 2
dy/dt = −0.2y, y(0) = 80, find y(5)Type the answer.
3 Question 3
dm/dt = −0.5m, m(0) = 40, find m(2)- A) 14.72
- B) 0
- C) 40
- D) −14.72
4 Question 4
dy/dt = −0.1y, y(0) = 50, find y(10)Type the answer.
5 Question 5
dy/dt = −0.2y, y(0) = 80, when is y = 20- A) t ≈ −6.93
- B) t ≈ 80
- C) t ≈ 6.93
- D) t ≈ 69.3
6 Question 6
dP/dt = kP, P(0) = 50, P(2) = 150, find kType the answer.
7 Question 7
dN/dt = kN, N(0) = 1000, N(3) = 1500, find N(6)- A) 1500
- B) 1000
- C) 2250
8 Question 8
dm/dt = −km, m(0) = 60, half-life 10, when is m = 15Type the answer.
9 Question 9
dy/dt = −0.3y, y(0) = 90, when is y = 10- A) t ≈ 90
- B) t ≈ −7.32
- C) t ≈ 7.32
- D) t ≈ 73.2
10 Question 10
dA/dt = 0.08A, A(0) = 2000, find A(12)Type the answer.