Not working with two digit answers

Hi,
I’m running a genesis theme and using captcha on my blog. I’m using a math problem for users to prove they are human. The thing is that the plug-in works great if the answer is a single digit. However, if it’s a double digit the form is not big enough to accommodate two number and it does not work. I’m trying to find out if this is a known issue with captcha or if it’s an issue with my theme. Please advise. P.S. Please hurry, I’m drowning in spam!!!

http://arewecrazyorwhat.net/dehydrate-tomatoes-plus-making-tomato-powder/

https://wordpress.org/plugins/captcha/