Adding three 2-digit numbers

Difficulty Stretch · Set qa5w8x

Fill in what you can and press Check. Nothing you type is sent anywhere.

1
293836+51
2
916257+51
3
954172+69
4
495052+84
5
761642+99
6
858726+88
7
372594+46
8
495838+82
9
797019+95
10
729197+68
11
557688+51
12
341254+79
13
305758+75
14
564210+18
15
128673+98
16
474952+82
17
199821+56
18
191743+97
19
679214+24
20
815284+64

What is in this set

The numbers in this set run from 10 to 99.
Every problem in it will stack more than two numbers.
99% of them need a carry into the next column.
A careful solution takes 5 written steps on average.
The mistake this set invites most often, in 100% of the problems: only the first two addends were added — the third column never joined in.
Answers are a whole number.

Drawing 240 problems from this page produced 240 different ones, 100% — so a sheet of 20 is a new sheet almost every time.

The same skill, harder or easier

We would put this in front of a grade 3 class. That is our judgement, not a standard, and it is printed here so you can disagree with it. Everything else we put in that year.