The video tutorial explains how to add weights of coins to find both an estimated and exact total. It begins with a problem involving two groups of coins weighing 20 grams and 39 grams. The tutorial first demonstrates estimating the total by rounding 39 to 40, making the addition easier, resulting in an estimated total of 60 grams. It then shows how to calculate the exact total using column addition, resulting in 59 grams. The lesson emphasizes checking units and writing the final answer with units. The video concludes by summarizing the process of adding whole measurements of weight.

Kayla initially has coins weighing 20 grams. How much do the additional coins from her dad weigh?

• 49 grams

• 29 grams

• 39 grams

• 19 grams

What is the estimated total weight of Kayla's coins when rounding 39 to 40?

• 80 grams

• 70 grams

• 60 grams

• 50 grams

Why is it easier to add 40 instead of 39 when estimating the total weight?

• 40 is a prime number

• 40 is more than 39

• 40 is less than 39

• 40 is a round number

What is the exact total weight of all the coins Kayla has?

• 58 grams

• 59 grams

• 60 grams

• 61 grams

When adding weights, why is it important to check the units?

• To ensure the numbers are even

• To make the numbers larger

• To avoid adding different types of measurements

• To make the addition faster