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Random number challenge 2


I'm having a hard time understanding what I did wrong here. I followed Dave's example in completing the random number challenge 2 in JavaScript Basics, but when I go to the web console I get a message saying "reference error: isNan is not defined". I can't see what I'm doing differently from the example given. Can anyone help? Here is my code and here is a snapshot of my workspace if that is easier to read. Thank you.


function getRandomNumber( lower, upper ) { if ( isNan(Lower) || isNaN(upper) ) { throw new Error('Both arguments must be numbers'); } return Math.floor(Math.random() * (upper - lower + 1)) + lower; }

console.log( getRandomNumber( 'nine', 24 ) ); console.log( getRandomNumber( 1, 100 ) ); console.log( getRandomNumber( 200, 'five hundred' ) ); console.log( getRandomNumber( 1000, 20000 ) ); console.log( getRandomNumber( 50, 100 ) );

1 Answer

28,558 Points

You have two typos in your code. Both related to differences in capitalization. JavaScript along with most programming languages is case-sensitive, meaning that Hello and hello are two entirely different words as far as it is concerned.

Specifically your typos are that the isNaN function ends with a capital N not a lowercase one like you use. And you also pass the first isNaN function an argument of Lower which should be lower with a lowercase letter to match the parameter named lower.