Arduino UNO + CC3000 Wifi Shield, Reading webpage data
Webpages usually return data in text format with new line characters at the end.
In case of 55 you would get "55\r\n" or [53, 53, 13, 10] in bytes.
You need to parse the characters, like Serial.parseInt() does.

You are also only sending every second byte back to the serial monitor and only saving the last byte from the other every second byte.
After you read a byte with Serial.read() you can't read the same byte again, you get the next one.
In case of 55 you would send back "5\r" to the serial monitor and only store "\n" or 10 into dollars.
In case of 0 you would send back "0\n" to the serial monitor and store some unknown value into dollars, because you read more bytes that was sent.