Below are three quick problems to help you apply what you learned. Create a new JavaScript file for each problem to practice building from scratch.

Problem 1: Determine the Sign of a Number

Objective: Write a script that determines if a number is positive, negative, or zero.

Instructions:

Declare a Variable:
- Create a variable number and assign it a numerical value.
Implement Conditional Logic:
- Use if, else if, and else statements to check whether the number is positive, negative, or zero.
Display the Result:
- Use console.log to output whether the number is positive, negative, or zero.

Problem 2: Grading System

Objective: Create a grading system that assigns letter grades based on score ranges.

Instructions:

Declare a Variable:
- Create a variable score and assign it a numerical value between 0 and 100.
Implement Conditional Logic:
- Use if, else if, and else statements to assign letter grades based on the following scale:
  - 90-100: A
  - 80-89: B
  - 70-79: C
  - 60-69: D
  - Below 60: F
Display the Grade:
- Use console.log to output the corresponding letter grade.

Problem 3: Eligibility Check

Objective: Determine eligibility for a senior citizen discount based on age.

Instructions:

Declare a Variable:
- Create a variable age and assign it a numerical value.
Implement Conditional Logic:
- Use if, else if, and else statements to check:
  - If age is 65 or above, display "Eligible for senior citizen discount."
  - If age is below 65, display "Not eligible for senior citizen discount."
Display the Result:
- Use console.log to output the eligibility status.

Objective:

Use if, else if, and else to choose an appropriate greeting based on the hour of the day.

Instructions:

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let hour = 14; // 24‑hour format, 0–23

Implement Conditional Logic
- If hour is between 5 (inclusive) and 12 (exclusive), greet “Good morning.”
- Else if hour is between 12 (inclusive) and 17 (exclusive), greet “Good afternoon.”
- Else if hour is between 17 (inclusive) and 21 (exclusive), greet “Good evening.”
- Else, greet “Good night.”
Display the Greeting

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console.log(greeting);

Objective:

Determine the ticket price based on a customer’s age.

Instructions:

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let age = 70;

Implement Conditional Logic
- If age is under 12, price is $5.
- Else if age is between 12 and 64 (inclusive), price is $12.
- Else (65 and older), price is $8.
Display the Price

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console.log(`Ticket price: $${price}`);

Objective:

Calculate a person’s Body Mass Index and classify their weight category.

Instructions:

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let weightKg = 70;   // in kilograms
let heightM   = 1.75; // in meters

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let bmi = weightKg / (heightM * heightM);

Implement Conditional Logic
- If bmi < 18.5, category is “Underweight.”
- Else if bmi < 25, category is “Normal weight.”
- Else if bmi < 30, category is “Overweight.”
- Else, category is “Obese.”
Display Results

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console.log(`BMI: ${bmi.toFixed(1)}, Category: ${category}`);

Day 6: Conditional Statements: If, Else If, Else