Different addition number sentences

This task is about finding the missing number in addition sentences.

Question 1Change answer

Write the missing number in each box in the following number sentences.
 
a) 9 + 8 =
 
b) 6 + =
11
 
c) + 12 =
19
 
d) 15 = +
7
 
e) = 3 +
9
 
f) 14 = 5 +