7. \( 3.8+1.4= \)

Did you know that the concept of addition goes back thousands of years, with the earliest recorded use in ancient Mesopotamia around 3000 BCE? They used a base-60 system, which profoundly influenced our modern understanding of numbers! When it comes to adding decimals, it’s essential to line up the numbers by their decimal points before performing the addition. So, for \(3.8 + 1.4\), you can visualize it like this: \(3.8\) is 3.80, and with \(1.4\) as 1.40, the addition becomes a breeze, resulting in \(5.2\)!