d. \( \frac{2}{3}+\frac{4}{9}= \)

To add \( \frac{2}{3} \) and \( \frac{4}{9} \), we first need a common denominator. The least common multiple of 3 and 9 is 9. We can convert \( \frac{2}{3} \) to \( \frac{6}{9} \) (by multiplying the numerator and denominator by 3). So, \( \frac{2}{3} + \frac{4}{9} = \frac{6}{9} + \frac{4}{9} = \frac{10}{9} \), which can also be written as \( 1 \frac{1}{9} \) if you prefer mixed numbers! Math has been around for thousands of years, evolving from ancient civilizations using simple counting methods to advanced concepts involving algebra, calculus, and statistics. The Babylonians and Egyptians left behind mathematical records that resemble some of our current practices, showcasing how human beings have always been curious about numbers! In real life, learning to add fractions doesn’t just come in handy during tests; it’s a skill you’ll use in cooking, crafting, and even budgeting! For instance, if you need to combine half a cup of sugar with two-thirds of a cup of sugar for a recipe, knowing how to add fractions will help you measure accurately and cook like a pro!