This chapter includes 33 problems covering 4 main topics, text blocks, locales, numbers, and mathematical operations. We will start with text blocks (elegant multiline strings introduced in JDK 13/15), continue with problems for creating Java Locale including localized locales (JDK 19, ofLocalizedPattern()), and finish with problems about numbers and math such as the Babylonian method for computing the square root and different corner cases of results overflow. The last part of the chapter is dedicated to JDK 17 new API for pseudo-random generators.