# Lesson Worksheet: Subtracting by Adding with Numbers up to 20 Mathematics • 1st Grade

In this worksheet, we will practice solving subtraction problems by finding the missing part in an addition expression with numbers up to 20.

Q1: He lost 6 of the cars.

He can work out how many cars are left by completing either number sentence:

How many cars are left?

Q2:

Isabella built 13 sandcastles on the beach. The tide came in and washed some of them away. There are 7 left and she wants to know how many were washed away. Which of these number sentences does she need to solve?

• A
• B
• C
• D

Which of these addition facts can help her to solve the problem?

• A
• B
• C

How many sandcastles were washed away?

Hint: Use to solve .

Q3:

Hannah and Anthony made 19 cupcakes.

After their dog ate some, there were 15 left. They want to know how many cakes their dog ate.

Who is correct? • Aonly Anthony
• BThey are both wrong.
• CThey are both correct.
• Donly Hannah

Q4:

We know that . What is ?

Q5:

We know that .

What is ?

Q6:

• A
• B
• C

What is the result of ?

Q7:

Q8:

Find the missing number in the given model. • A
• B
• C

Q9:

Which of the following calculations can help you check if is correct?

• A
• B
• C