Rocky family recipe for macaroni and cheese makes 4 servings of 310 calories each. rocky decided to make 1.5time the recipe. how many calories, are in rocky batch of mac and cheese

There are 4 servings with 310 calories in each serving
310×4=1,240 calories altogether
Since any number times 1 is the number, you just focus on the .5
.5 is also which is half of a number
1,240×.5=620
1,240+620=1,860
There are 1,860 calories in the batch

This is the more deconstructed, longer way in doing it
So an easier way is simply multiply 1,240×1.5=1,860