A desk calculator is a device that helps us do math, like adding or subtracting numbers. An expensive desk calculator is one that costs a lot of money because it has many features that make math even easier, accurate and fast.
For example, a regular calculator has basic functions like addition, subtraction, multiplication and division. An expensive desk calculator can have special functions that help us with advanced math, like square roots, trigonometry, or even calculus.
These fancy calculators are also made with high-quality materials and have a strong build, which makes them durable and long-lasting, so they can be used for a longer time.
Moreover, expensive desk calculators can also have bigger and clearer displays, colorful buttons with symbols or shapes on them to make it easier to press the right buttons. Some may even have touchscreens and styluses like a phone or tablet, so you can easily swipe and click around the calculator.
In simple terms, an expensive desk calculator is like a very smart and durable calculator that can do more advanced math and has special features that make math easier and faster.