Answer:
Let's look at the whole numbers first and put aside the decimals;
38 and 7, let's add these two: 38 + 7 = 45
Now let's look at the decimals;
0.42 and 0.10, let's add these two:
0 . 4 2
0 . 1 0
+ _______
0. 52 → Next, we add the decimals and the whole numbers:
45 + 0.52
= 45.52, 45.52 is your answer.