How to add two decimal places to an array of objects

The array looks like this:

const arr = [
    {title: 'Cat1', val1: '0', val2: '20'},
    {title: 'Cat2', val1: '0', val2: '30'},
]

I need the val1 and val2 to be converted into a number with two decimal places (eg. 0.00, 20.00), and then be able to pass the treated array (that includes everything else) in a different function.