Cathy think 1,275 rounded to the nearest hunded is 1,200 because 2 is less than 5 what might be Cathy misundertanding about rounding

That 1,275 is rounded to the nearest hundred is 1,300 because 75 is bigger than 50 or 5

Cathy may not understand that you look at the neighbor of your number which is seven and anything with the number 4 or less will stay the same. Which would get you 1,200 anything 5 or more you will raise the number which means that the number 1,275 rounded to the nearest hundredth would be 1,300.