Missing number in a 2-digit subtraction

Difficulty Starter · Set dns444

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

1
70−=67
2
71−=67
3
52−=48
4
52−=43
5
20−=12
6
26−=19
7
62−=58
8
74−=69
9
31−=23
10
40−=36
11
105−=96
12
101−=96
13
71−=67
14
73−=69
15
45−=38
16
73−=65
17
21−=14
18
105−=98
19
63−=55
20
85−=78

What is in this set

The numbers in this set run from 11 to 108.
Every problem in it will need a borrow from the column to the left.
A careful solution takes 2 written steps on average.
The mistake this set invites most often, in 100% of the problems: the two numbers on the page were added — a missing part is found by taking one away from the total, not by adding.
Answers are a whole number.

Drawing 240 problems from this page produced 172 different ones, 72% — 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.