What is The Number 87?

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Grade Level:

Pre-School – Class 2

All domains without exception

Definition

What is it?

The number 87 is a two-digit natural number that comes after 86 and before 88. It is made up of 8 tens and 7 ones. Eighty-seven is an odd number, meaning it cannot be divided exactly by 2.

Simple Example

Quick Example

Imagine your school bus has 87 seats. This means 87 students can sit in the bus. If 80 students are already sitting, then 7 more students can still find a seat.

Worked Example

Step-by-Step

Let's find out how many cricket balls are needed if each team needs 87 balls for practice, and there are 2 teams. --- Step 1: Identify the number of balls needed per team: 87. --- Step 2: Identify the number of teams: 2. --- Step 3: To find the total, we multiply the number of balls per team by the number of teams: 87 x 2. --- Step 4: Multiply the ones digit: 7 x 2 = 14. Write down 4 and carry over 1. --- Step 5: Multiply the tens digit: 8 x 2 = 16. Add the carried over 1: 16 + 1 = 17. --- Step 6: Combine the results. The total number of balls needed is 174. --- Answer: 174 cricket balls.

Why It Matters

Understanding numbers like 87 is fundamental to all of mathematics and science. It helps you count, measure, and solve problems in daily life. Engineers use numbers to design bridges, and scientists use them to understand the universe.

Common Mistakes

MISTAKE: Confusing 87 with 78. | CORRECTION: Remember that the first digit (8) tells you the 'tens' and the second digit (7) tells you the 'ones'. So, 87 is 'eighty-seven', not 'seventy-eight'.

MISTAKE: Thinking 87 is an even number. | CORRECTION: An even number can be divided by 2 without any remainder. 87 divided by 2 leaves a remainder of 1, so it is an odd number.

MISTAKE: Incorrectly writing 87 in words as 'eighty and seven'. | CORRECTION: The correct way to write 87 in words is 'eighty-seven'.

Practice Questions

Try It Yourself

QUESTION: If you have 87 rupees and your friend has 10 rupees less than you, how much money does your friend have? | ANSWER: 77 rupees

QUESTION: A train has 87 passengers. At the next station, 13 passengers get off and 5 passengers get on. How many passengers are now on the train? | ANSWER: 79 passengers

QUESTION: Can 87 mangoes be shared equally among 3 friends without cutting any mangoes? Show your working. | ANSWER: Yes, 87 divided by 3 is 29. Each friend gets 29 mangoes.

MCQ

Quick Quiz

Which of the following statements about the number 87 is TRUE?

It is an even number.

It comes after 88.

It is made of 8 tens and 7 ones.

It is written as 'seventy-eight' in words.

The Correct Answer Is:

The number 87 is an odd number, not even. It comes before 88, not after. It is written as 'eighty-seven'. Option C is correct because 87 literally means 8 groups of ten and 7 single units.

Real World Connection

In the Real World

You see numbers like 87 every day. For example, your mobile phone's battery percentage could be 87%. Or, if you are buying groceries, the total bill might come up to 87 rupees. Even your favorite cricket player's score could be 87 runs!

Key Vocabulary

Key Terms

NATURAL NUMBER: A counting number starting from 1 (1, 2, 3...). | TWO-DIGIT NUMBER: A number made up of two digits, like 10, 25, 87. | ODD NUMBER: A whole number that cannot be divided exactly by 2. | TENS PLACE: The position of a digit representing groups of ten. | ONES PLACE: The position of a digit representing single units.

What's Next

What to Learn Next

Now that you understand what the number 87 is, you can explore larger numbers and learn about place value in more detail. This will help you count and work with even bigger numbers easily.