Add Multiples of 10

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Add Multiples of 10 · Grade 1 · Worksheet 3

1. Max has 40 stickers. Max's friend gives Max 30 more stickers. How many stickers does Max have in all? Answer: 70 Solution: Max starts with 40 stickers. Max receives 30 more stickers. Add them together: 40 + 30 = 70.
   Full step-by-step solution

   Step 1: Max starts with 40 stickers. Step 2: Max receives 30 more stickers. Step 3: Add them together: 40 + 30 = 70. Max has 70 stickers in all.

2. Noah has 40 toy cars in his collection. For his birthday, he gets 50 more toy cars. How many toy cars does Noah have now? Answer: 90 Solution: Noah starts with 40 toy cars. He gets 50 more toy cars. Add the two amounts: 40 + 50 40 + 50 = 90 Noah has 90 toy cars now.
   Full step-by-step solution

   Step 1: Noah starts with 40 toy cars. Step 2: He gets 50 more toy cars. Step 3: Add the two amounts: 40 + 50 Step 4: 40 + 50 = 90 Noah has 90 toy cars now.

3. 60 + 30 = ? Answer: 90 Solution: Look at the tens place in both numbers. 60 has 6 tens, and 30 has 3 tens. Add the tens together: 6 tens + 3 tens = 9 tens.
   Full step-by-step solution

   Step 1: Look at the tens place in both numbers. 60 has 6 tens, and 30 has 3 tens. Step 2: Add the tens together: 6 tens + 3 tens = 9 tens. Step 3: 9 tens is the same as 90. The answer is 90.

4. A baker made 20 cookies in the morning and 50 cookies in the afternoon. How many cookies did the baker make in total? Answer: 70 Solution: The baker made 20 cookies in the morning. The baker made 50 cookies in the afternoon. Add the morning and afternoon cookies: 20 + 50 20 + 50 = 70 The answer is 70.
   Full step-by-step solution

   Step 1: The baker made 20 cookies in the morning. Step 2: The baker made 50 cookies in the afternoon. Step 3: Add the morning and afternoon cookies: 20 + 50 Step 4: 20 + 50 = 70 The answer is 70.

5. Amelia has 50 stickers. Amelia's friend gives Amelia 10 more stickers. How many stickers does Amelia have in all? Answer: 60 Solution: Amelia starts with 50 stickers. Amelia receives 10 more stickers. Add them together: 50 + 10 = 60.
   Full step-by-step solution

   Step 1: Amelia starts with 50 stickers. Step 2: Amelia receives 10 more stickers. Step 3: Add them together: 50 + 10 = 60. Amelia has 60 stickers in all.

6. Liam has 20 stickers in his collection. His friend Emma gives him 30 more stickers. How many stickers does Liam have now? Answer: 50 Solution: Liam starts with 20 stickers. Emma gives him 30 more stickers. To find the total number of stickers Liam has now, we add the stickers he started with to the stickers Emma gave him.
   Full step-by-step solution

   Liam starts with 20 stickers. Emma gives him 30 more stickers. To find the total number of stickers Liam has now, we add the stickers he started with to the stickers Emma gave him. Step 1: Write the addition expression. 20 + 30 Step 2: Add the numbers. First, add the tens: 20 has 2 tens, 30 has 3 tens. 2 tens + 3 tens = 5 tens, which is 50. So, 20 + 30 = 50. Step 3: State the final answer. Liam now has 50 stickers.

7. Harper picked 10 flowers from the garden in the morning and 30 flowers in the afternoon. How many flowers did Harper pick altogether? Answer: 40 Solution: Harper picks 10 flowers in the morning. Harper picks 30 flowers in the afternoon. Add the two amounts: 10 + 30 = 40.
   Full step-by-step solution

   Step 1: Harper picks 10 flowers in the morning. Step 2: Harper picks 30 flowers in the afternoon. Step 3: Add the two amounts: 10 + 30 = 40. Harper picked 40 flowers altogether.

8. A triangle has 3 sides. One side is 10 cm long, another side is 20 cm long, and the third side is 30 cm long. What is the total length of all three sides of the triangle? Answer: 60 Solution: The first side is 10 cm long. The second side is 20 cm long. Add this to the first side: 10 + 20 = 30.
   Full step-by-step solution

   Step 1: The first side is 10 cm long. Step 2: The second side is 20 cm long. Add this to the first side: 10 + 20 = 30. Step 3: The third side is 30 cm long. Add this to the total so far: 30 + 30 = 60. The total length of all three sides is 60 cm.

9. Liam collected 20 seashells at the beach in the morning. In the afternoon, he found 30 more seashells. How many seashells did Liam collect in total? Answer: 50 Solution: Identify the number of seashells collected in the morning. Liam collected 20 seashells in the morning. Identify the number of seashells collected in the afternoon.
   Full step-by-step solution

   Step 1: Identify the number of seashells collected in the morning. Liam collected 20 seashells in the morning. Step 2: Identify the number of seashells collected in the afternoon. Liam found 30 more seashells in the afternoon. Step 3: Add the seashells from both parts of the day to find the total. We add the morning seashells and the afternoon seashells: 20 + 30 Step 4: Perform the addition. 20 + 30 = 50 Step 5: State the final answer. Liam collected 50 seashells in total.