task 2 overflow?

[stchang]

Something strange happens when celsius box has a large value. For example, type in 100000000000000000000000 (1 followed by 23 zeros). After typing the 23rd zero, the value in the text box changes to 99999999999999991611392. Is some kind of overflow happening?

Other observations:

• Deleting the last number restores the value to 100000000000000000000000 (1 followed by 22 zeros)
• The behavior still occurs even when the value is pasted into the text box.

Tested with ubuntu linux and racket 7.5