Page 235 - Web Applications (803) Class 12
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24. Write a function in JavaScript that accepts two integer variables and returns their sum. [2022 T2]
function add(n1,n2){
var sum=n1+n2;
return sum;
}
var result=add(10,12);
document.write("The sum is "+result);
25. Explain the term inner function in JavaScript with an example. [2022 T2]
Ans. JavaScript supports nested functions i.e., functions defined inside another function. Only statements in the outer
function can access the inner function. The inner function can make use of the arguments and variables of the
outer function. However, the outer function cannot make use of the inner function's arguments and variables.
<script>
function add() {
let ctr = 10;
function inc() {ctr=ctr-1;}
inc(); //call to inner function
return ctr;
}
document.write(add()); //call to outer function
</script>
Output: 9
26. Explain the use of the reverse method in JavaScript. Write a function 'Revrs' in JavaScript to explain reverse the
order of elements in a given array. [2022 T2]
Ans. The reverse() method in JavaScript is used to reverse the order of elements in an array. It modifies the original
array in place, meaning it changes the order of elements without creating a new array.
var Arr = [10, 20, 33, 44, 50];
document.write(Arr.reverse());
Output: 50,44,33,20,10
27. Write a program in JavaScript that accepts three numbers from the user and displays the average
value. [2022 T2]
Ans. <script>
// Prompt the user to enter three numbers
var num1 = parseFloat(prompt("Enter the first number:"));
var num2 = parseFloat(prompt("Enter the second number:"));
var num3 = parseFloat(prompt("Enter the third number:"));
// Calculate the average
var average = (num1 + num2 + num3) / 3;
// Display the result
document.write("The average is "+ average);
</script>
Web Scripting—JavaScript 233

