The number she'd have is:
560
Step-by-step explanation:
First, let's see which number is in the tens place and which number is in the ones place (the units place).
In the number 548, the place value of 5 is hundreds, the place value of 4 is tens, and the place value of 8 is ones (or units).
So if Sera adds two to the units, she'll have 10. But, since we can't write the number as 5410 (that would be a totally different number), we just write 0 in the units place, and shift 1 to the tens place, which gives us :
550
That's not all, since we also add 1 to the tens:
560
Hence, Sera ends up with 560.