Lists Exercises

Lists Exercises#

Question-1#

Create a list with the elements: \(10, 20, 30, 40, 10, 20, 30, 10, 20\) and print the following information about this tuple:

The number of occurrences of 30.
The element at index 5.
The third element.
The index of the first occurrence of 20.
The index of the second occurrence of 20.
The index of the third occurrence of 20.
The length (number of elements) of the list.
The maximum, minimum, and the sum of the elements.
The last four elements using slicing.
The first five elements using slicing.

Question-2#

Create a list with the elements: \('a', 5, 8, 'b'\) and perform the following operations on it, printing it after each operation:

Add 99.
Add 100 as the second element to the list.
Add all elements from the list [2, 6, 5, 9, 1, 1, 5].
Remove ‘a’ using the pop() method.
Remove ‘b’ using the remove() method.
Reverse the order of the list.
Sort it in ascending order.
Sort it in descending order.

Question-3#

Store the unique values in the following list into a list and sort them.

numbers = [9, 4, 10, 9, 9, 2, 7, 9, 8, 6, 4, 6, 10, 5, 1, 7, 7, 5, 9, 2, 5]

Question-4#

Generate a list containing numbers from 4 to 9, inclusive.

Construct a multiplication table for these numbers to resemble a 6 by 6 matrix and print it.
Store all sum of the values in each row in this multiplication table into a list.

Question-5#

Use list comprehension and random.randint() to construct two lists:

Generate ten random numbers between 1 and 20, stored in a list called left_list.
Generate ten random numbers between 1 and 10, stored in a list called question_list.
Create a new list called right_list, consisting of the differences between 30 and the sum of corresponding numbers in left_list and question_list.
For each line, print dashes (-) equal to the number in left_list, followed by question marks equal to the number in question_list, and then dashes equal to the number in right_list.

Sample Output Only first line out of 10.

\(--------------????------------\)

Question-6#

Choose a random 6-digit number and store its unique digits in a list as integers and in descending order.

Display the number and its unique digits.
Avoid the use of sets.
Sample Output:
- The unique digits of 166464 are [6, 4, 1]

Question-7#

Choose a random 6-digit number and verify if all of its digits are distinct.

Avoid the use of sets.
Sample Output:
- The number 986728 contains repeated digits.
- The number 362951 has distinct digits.

Question-8#

Choose a random 6-digit number whose digits are distinct.

Avoid the use of sets.

Question-9#

Choose ten random 6-digit numbers whose digits are distinct and store them in a list as integers.

Avoid the use of sets.

Question-10#

Choose two random 6-digit numbers whose digits are distinct and store them in a list as integers.

Store the common digits of these two numbers in a list.
Avoid the use of sets.
Sample Output:
- The common digits of 479310 and 706843 are [4, 7, 3, 0]

Question-11#

Choose two random 6-digit numbers with distinct digits and store them as integers in a list.

Store the common digits of these two numbers in another list.
Initialize two count variables with an initial value of zero: count_negative and count_positive.
If a common digit appears in the same position in both numbers, increase count_positive by one.
If a common digit appears in different positions in both numbers, decrease count_negative by one.
Avoid the use of sets.
Sample Output-1:
- The common digits of 247583 and 579063 are [7, 5, 3].
- Positive Count: 1 — Negative Count: -2
Sample Output-2:
- The common digits of 470829 and 926504 are [4, 0, 2, 9].
- Positive Count: 0 — Negative Count: -4
Sample Output-3:
- The common digits of 298731 and 928051 are [2, 9, 8, 1].
- Positive Count: 2 — Negative Count: -2

Question-12#

Prompt the user to input comma-separated integers of their choice.

Use the split() method of strings to store the numbers in a list.
Print the type of the first number in this new list.
Use a list comprehension to generate a new list with all these numbers in integer type.
Print the sum of all these numbers.

Question-13#

For the lists given below, begin with the total list initialized as [0, 0, 0].

grade_level = [ 9,  9, 10, 11, 10, 10,  9, 10, 11, 11, 10, 11,  9, 11, 11,  9, 10, 10, 10, 10]
exam_result = [59, 20, 81, 30, 62, 56, 85, 72, 48, 15, 47, 18, 11, 37, 79, 87, 79, 92, 82, 66]

Use a for loop to add each:

9th grader’s exam result to the index 0 position of the total list.
10th grader’s exam result to the index 1 position of the total list.
11th grader’s exam result to the index 2 position of the total list. The final version of the total list should be: [sum of 9th graders’ exam results, sum of the 10th graders’ exam results, sum of the 11th graders’ exam results].

Question-14#

For the lists given below, calculate the average exam grades for each grade level and visualize them using a bar graph.

grade_level = [ 9,  9, 10, 11, 10, 10,  9, 10, 11, 11, 10, 11,  9, 11, 11,  9, 10, 10, 10, 10]
exam_result = [59, 20, 81, 30, 62, 56, 85, 72, 48, 15, 47, 18, 11, 37, 79, 87, 79, 92, 82, 66]

Business Applications#

Question: Max of Revenue#

Revenue (R) is the product of the number (n) of items sold and the price (p) of the item.

\(R = p\cdot n\)

The number of item sold is given by the following equation: \(n = -1.5p+30\)

Construct a list that consists of the revenues for \(0\le p \le 20\).
Plot the graph of revenue for \(0\le p \le 20\)

Question: Profit#

Profit (P) is the difference between Revenue and Cost

\(Profit = Revenue - Cost\)

The monthly fixed cost of a cable factory is 1500 dollars. Each cable costs 13 dollars and sells for 25 dollars.

For what number of cables produced profit is zero.
- Hint: Calculate the profit for \(n\) between 1 and 400.
Construct three lists that consist of the revenues, costs, and profits for \(0\le p \le 400\).
Plot the reveue, cost, profit for producing up to 400 cables.
Draw a vertical line where the profit is zero for \(n\).

Sample Plot:

Question: Break-Even Point#

Break-Even Point is the point where total cost equals total revenue, meaning profit is zero.

For the given cost and the revenue functions find the break-even point and plot it.

\(C(n) = 0.5n +2000\)

\(R(n) = 2.5n\)

Hint: Calculate the cost and revenue for n between 1 and 10,000.

Sample Plot:

Question: Exponential Depreciation#

The value \(V\) of a truck in dollars is given by the formula \(V(t)=140000(1.35)^{-0.6t}\) where \(t\) is the age of the truck in years.

Plot the graph of values of the truck in 30 years.

Question: Demand#

If the demand function is given as the following linear relation \(p = -2q+300\).

Plot the demand function for \(1\le q\le 200\).

Question: Supply Function#

If the supply function is given by the linear relation \(p = 4q+100\).

Plot the supply function for \(1\le q\le 100\).

Question: Equilibrium Point#

An equilibrium point is where the demand and supply curves intersect.

For the given demand and the supply functions find the equilibrium point and plot it.

Demand: \(p(q) = -0.03q + 1000\)

Supply: \(p(q) = 0.02q + 400\)

Hint: Calculate the demand and supply for \(q\) between 0 and 20,000.

Sample plot:

Question: Stock Percentage Changes#

The following is a list of the prices for Tesla stock over a certain period of time.

stock_prices = [174.9499969482422,
60000610351562,
11000061035156,
74000549316406,
24000549316406,
75,
19000244140625,
7899932861328,
0800018310547,
2899932861328,
77000427246094,
0,
94000244140625,
47999572753906,
7899932861328,
66000366210938,
2899932861328,
47000122070312,
00999450683594,
44000244140625,
86000061035156]

Create a list of percentage changes using the stock_prices list.

The first element of the percentage list is np.nan because there is no price available for the previous day.

Question: Stock Behavior#