Find the value of each sum.
Show your thinking using drawings, numbers, or words.

1. \(47 + 3\)

2. \(47 + 8\)

Find the value of each sum.
Show your thinking using drawings, numbers, or words.

1. \(78 + 6 \)

2. \(6 + 78 \)

Find the value of each sum.
Show your thinking using drawings, numbers, or words.

1. \(63 + 5\)
2. \(63 + 8 \)

3. How are the problems alike?

   How are they different?

Exploration

Choose 5 numbers from below to make a sum with a value greater than 50 but less than 99.

Use equations or drawing to show your thinking.

Here is how Lin found the value of \(58 + 9\).

“I know \(8 + 9 = 17\). Then I add 5 tens and get 67.”

1. Why does Lin's method work?
   Show your thinking using drawings, numbers, or words.

2. Use Lin's method to find the value of \(83 + 8\).

Noah’s brother spilled water on his math work.
Help Noah figure out the unknown number.

1. The unknown number makes the value of the sum greater than 50. The sum has a 0 in the ones place.

   

   What could the unknown number be?

2. The unknown number is a 2-digit number.
   It makes the value of the sum 75.

   

   What could the unknown number be?

3. The unknown number is a 2-digit number.
   It makes a value that is more than 80 but less than 90.

   

   What could the unknown number be?

Priya is playing the game Target Numbers.
Priya starts at 25. She picks these 6 cards:

She chooses to add that many tens or ones for each card.
What is the highest score she can get without going over 95?
Use equations to show your thinking.