Counting by tens means you add 10 each time. Therefore, after 30, the next number is 40. This pattern helps build numerical fluency.

Adding 10 to 20 gives 30. This follows the counting by tens pattern, reinforcing the concept that each step increases by 10.

The tens counting sequence includes numbers that are multiples of 10. 30 is a multiple of 10, so it is in the sequence. The other options are not multiples of 10.

Adding 10 to 0 gives you 10. This simple addition is the foundation of counting by tens, reinforcing the idea of consistent increments.

10 plus 10 equals 20. This basic arithmetic reinforces the process of counting by tens. It confirms an understanding of simple addition in the tens series.

The sequence begins at 10 and each subsequent number increases by 10. Counting: 10 (1st), 20 (2nd), 30 (3rd), 40 (4th), 50 (5th). Thus, the correct answer is 50.

Starting from 0 and counting by tens gives 0 as the first number, then 10, 20, 30, 40, 50, and 60. Therefore, the 7th number in the sequence is 60.

Multiplying the number of packs by the number of stickers per pack gives the total number of stickers. In this case, 3 multiplied by 10 equals 30. This reinforces understanding of multiplication via the tens sequence.

70 divided by 10 equals 7, meaning there are 7 tens in 70. This helps in understanding the concept of place value. Recognizing multiples of ten is fundamental for number fluency.

Adding 10 four times to 30 results in 70. This demonstrates the additive property of the tens sequence. It reinforces the idea of sequential addition.

Subtracting 10 from 100 gives 90. This simple subtraction reinforces the pattern in counting by tens. It further strengthens basic arithmetic skills.

Multiplying 10 by 6 results in 60. This problem connects multiplication with the concept of adding tens repeatedly. It reinforces the structure of the tens sequence.

The series increases by 10 each time. The number between 20 and 40 should be 30. This tests the ability to identify patterns within the tens sequence.

The total sum of 20, 30, and 40 is 90. This problem combines addition with recognition of multiples of ten. It reinforces both arithmetic skills and sequential counting.

Among the pairs provided, 30 plus 70 gives 100. The other pairs do not sum to 100. This exercise reinforces the concept of combining multiples of ten through addition.

If Jenny saves $10 every week, multiplying 10 by the number of weeks gives the total amount saved. Solving 10 x weeks = 100 yields 10 weeks. This applies the tens counting concept to a real-life scenario.

The area of a rectangle is calculated by multiplying its length by its width. Multiplying 70 by 30 results in 2100 square feet. This problem applies multiplication of multiples of ten in a practical context.

One hour has 60 minutes, which contains six 10‑minute intervals. Since the car travels 10 miles per interval, multiplying 6 by 10 gives 60 miles. This reinforces understanding of consistent groups of tens.

Using the arithmetic series formula, the sum is calculated as (first term + last term) multiplied by the number of terms divided by 2. For this series, (10 + 100) multiplied by 10 divided by 2 equals 550. This integrates sequential counting with summation concepts.

Dividing the total number of desks by the number of desks per row gives the number of rows. In this case, 80 divided by 10 equals 8. This question combines practical reasoning with fundamental arithmetic using multiples of ten.