This calculator is designed to perform the four basic arithmetic operations: addition, subtraction, multiplication, and division. These operations are the fundamental building blocks of mathematics and are used in countless real-world scenarios, from balancing your checkbook to complex scientific computations.
The Operations Explained:
Addition (+): Combines two or more numbers to find their total sum. For example, 5 + 3 = 8.
Subtraction (-): Finds the difference between two numbers. It's essentially adding the inverse. For example, 10 – 4 = 6.
Multiplication (*): A shortcut for repeated addition. For example, 3 * 4 means adding 3 to itself 4 times (3 + 3 + 3 + 3), which equals 12.
Division (/): Splits a number into equal parts or determines how many times one number is contained within another. For example, 12 / 3 = 4, meaning 3 goes into 12 four times.
How the Calculator Works:
The calculator takes two numbers and a selected operation as input. It then applies the chosen mathematical rule to these numbers:
If you select '+', it adds the second number to the first.
If you select '-', it subtracts the second number from the first.
If you select '*', it multiplies the first number by the second.
If you select '/', it divides the first number by the second. A critical edge case is division by zero, which is mathematically undefined. Our calculator includes a check to prevent this error and will display an appropriate message.
Use Cases:
Even the simplest calculator has practical applications:
Everyday Calculations: Splitting a bill at a restaurant, calculating distances, or figuring out cooking ingredient ratios.
Basic Budgeting: Adding up expenses or subtracting costs.
Learning and Education: Helping students practice and understand fundamental arithmetic.
Quick Estimates: Performing rapid mental math checks for various scenarios.
By providing a straightforward interface for these core operations, this calculator aims to be an accessible tool for anyone needing to perform quick and accurate mathematical calculations.
function calculateResult() {
var num1 = parseFloat(document.getElementById("number1").value);
var num2 = parseFloat(document.getElementById("number2").value);
var operator = document.getElementById("operator").value;
var result = "";
var resultValueElement = document.getElementById("result-value");
var resultDisplayElement = document.getElementById("result");
if (isNaN(num1) || isNaN(num2)) {
result = "Please enter valid numbers.";
resultValueElement.innerText = "";
} else {
if (operator === "add") {
result = num1 + num2;
} else if (operator === "subtract") {
result = num1 – num2;
} else if (operator === "multiply") {
result = num1 * num2;
} else if (operator === "divide") {
if (num2 === 0) {
result = "Error: Division by zero is not allowed.";
resultValueElement.innerText = "";
} else {
result = num1 / num2;
}
}
if (result !== "" && !isNaN(result)) {
resultValueElement.innerText = result;
} else if (result !== "") {
// Handle specific error messages from division by zero
resultDisplayElement.innerText = result;
return; // Exit early to prevent overriding error message
}
}
if (result !== "") {
resultDisplayElement.innerText = "Your result is:";
resultValueElement.innerText = result;
} else {
resultDisplayElement.innerText = "Please enter valid numbers and select an operation.";
resultValueElement.innerText = "";
}
}