Set 17: Linear Equations (Intermediate)

Choice D is correct. Choice C is the correct answer. This is a practical problem involving nice round numbers. 1. Start with the equation: $x + 47 = 100$ 2. Subtract 47 from both sides: $x = 100 - 47$ 3. Calculate: $x = 53$ 4. Verify: $53+ 47 = 100$ ✓ Mental Math: You can think of this as "what number plus 47 equals 100?" Counting up from 47 to 100 gives you 53. Choice A is incorrect because this results from adding instead of subtracting: $100+ 47 = 147$. This is the wrong inverse operation. Choice C is incorrect because this confuses the constant (47) with the solution. Just because 47 appears in the equation doesn't make it the answer. Choice D is incorrect because this results from dividing: $\frac{100}{47} \approx 2.13$. Division is not relevant for this addition equation.