What is Seventy?

S0-SA1-0588

Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

Seventy is the natural number that comes after sixty-nine (69) and before seventy-one (71). It is written as '70' in digits and 'seventy' in words. It represents a quantity of seven tens.

Simple Example

Quick Example

Imagine you have 7 groups of 10 cricket balls each. If you count all the balls together, you will have seventy cricket balls. So, 7 x 10 = 70.

Worked Example

Step-by-Step

PROBLEM: Your school library has 7 shelves, and each shelf can hold 10 books. How many books can all 7 shelves hold in total?

Step 1: Understand the problem. We need to find the total number of books.
---Step 2: Identify the given information. There are 7 shelves.
---Step 3: Identify how many books each shelf holds. Each shelf holds 10 books.
---Step 4: To find the total, we multiply the number of shelves by the number of books per shelf.
---Step 5: Calculation: 7 shelves * 10 books/shelf = 70 books.
---Step 6: State the answer clearly.

ANSWER: The 7 shelves can hold a total of 70 books.

Why It Matters

Understanding numbers like seventy is fundamental to all of mathematics and science. It helps you count money, measure distances, and even understand data in fields like business and engineering. Many careers, from a shopkeeper to an astrophysicist, rely on solid number sense.

Common Mistakes

MISTAKE: Writing 'seventy' as '7T' or '7ty' | CORRECTION: Always write the number '70' in digits and 'seventy' in words.

MISTAKE: Confusing seventy (70) with seventeen (17) | CORRECTION: Remember that 'seventy' has a 'ty' sound at the end, meaning 7 tens. 'Seventeen' has a 'teen' sound, meaning 1 ten and 7 ones.

MISTAKE: Thinking 7+0 = 70 | CORRECTION: Adding 7 and 0 gives 7. Seventy means 7 groups of ten, or 7 x 10.

Practice Questions

Try It Yourself

QUESTION: If you have 7 ten-rupee notes, how much money do you have in total? | ANSWER: 70 rupees

QUESTION: A bus can carry 70 passengers. If 35 passengers are already inside, how many more can get in? | ANSWER: 35 more passengers (70 - 35 = 35)

QUESTION: Your grandmother is 70 years old. Your grandfather is 5 years older than her. How old is your grandfather? | ANSWER: 75 years old (70 + 5 = 75)

MCQ

Quick Quiz

Which of these represents the number seventy?

Seven tens

Seven ones

Seventy-one

Seventeen

The Correct Answer Is:

Seventy means seven groups of ten, which is 7 x 10. Seven ones is 7. Seventy-one is 71. Seventeen is 17.

Real World Connection

In the Real World

When you check your mobile data usage, you might see you've used 70% of your daily limit. Or, if you're planning a train journey, the distance between two cities might be 70 kilometers. Even a cricket team's score can reach 70 runs in an exciting match!

Key Vocabulary

Key Terms

NUMBER: A count or quantity | DIGIT: A single symbol used to write numbers (0, 1, 2...9) | TENS PLACE: The second digit from the right in a number, representing groups of ten | QUANTITY: How much of something there is

What's Next

What to Learn Next

Now that you understand seventy, you're ready to explore larger numbers and place value in more detail. Next, you can learn about 'What is Place Value?' to understand how the position of a digit changes its value, which is crucial for all calculations.