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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge, Part II Solution

Osas Oyara
Osas Oyara
2,355 Points

Im getting the error that isNan is not defined.

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( 1, 6) ); console.log( getRandomNumber( 'nine', 25) ); console.log( getRandomNumber( 1, 100) );

1 Answer

Hello there! So you just have a syntax error. You are writing isNan() but it should be isNaN().

I looked it up in the documentation for isNaN(): https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN

I hope this helps!