Tristen is building 3 trophies using Legos. He needs 324 total Legos. Tristen uses 220 Legos for the largest trophy and 135 Legos for the smallest trophy. How many Legos will he use to build the final trophy

166 legos are required

Step-by-step explanation:

In this case, let's analyze the data. We need 3 trophies, using at most 324 legos in total. The big trophy requires 220 legos, the smallest requires 135, so we need to know how much will be used in the medium trophy. This number should be 135 < X < 220

Now, if we know that the total legos to be used are 324, then, we can make a difference and sum for all the legos, and then, calculate the number of legos used.

Total legos = A + B + C

324 = 220 + 135 + C

324 = 355 + C

C = -31

This means that there is difference of 31 legos between the smallest and biggest trophy, therefore, this difference should be used and added to the smallest trophy and see how much Tristen use in the final trophy:

135 + 31

= 166 legos

So we need to use 166 legos to build the final trophy.