Standard One Mathematics – Arithmetic Notes

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Topic: Arithmetic

Arithmetic is an elementary branch of mathematics that deals with numerical operations like addition, subtraction, multiplication, and division. In a wider sense, it also includes exponentiation, extraction of roots, and taking logarithms.

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1. Using Numbers to Communicate in Different Situations

• We use numbers to tell how many things we have.

  1. Example: I have 2 apples.

  2. Example: Today is Monday, the 1st day of the week.

• We use numbers to show order.

  1. Example: I am the 3rd in the line.

  2. Example: Today is the 16th day of the month.

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2. Using Numbers in Daily Life

• We use numbers every day to:

  1. Count things: 1, 2, 3…

  2. Add things: If I have 2 pencils and get 1 more, I have 3 pencils.

  3. Subtract: If I have 3 sweets and eat 1, I have 2 sweets left.

• We also use numbers when:

  1. Buying things (money)

  2. Cooking (measuring ingredients)

  3. Telling time

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3. Using Measurement Skills in Daily Life

• We measure:

  1. Length: How long or short something is.
     Example: This pencil is short.

  2. Weight: How heavy something is.
     Example: The watermelon is heavy.

  3. Time: Morning, afternoon, evening.
     Example: We go to school in the morning.

• Simple units we learn:

  1. Day, hour, minute

  2. Tall, short

  3. Heavy, light

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4. Using Shape Skills in Daily Life

• We see shapes every day!

  1. Circle: Like a ball or a plate

  2. Square: Like a window or a box

  3. Rectangle: Like a door or a book

  4. Triangle: Like a slice of pizza or a roof

• We learn to:

  1. Name the shape

  2. Draw the shape

  3. Compare shapes (big, small, same, different)

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5. Using Data Skills to Share Information

• We collect information and use it to:

  1. Count how many people like bananas

  2. Count how many boys and girls are in the class

• We can draw:

  1. Tally marks

  1. Simple charts
     Example: More children like mangoes than oranges.

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6. Using Arrangement Skills to Solve Daily Problems (Patterns and Sequences)

• We arrange things to help us solve puzzles.
  Example: Red, blue, red, blue… What comes next? (Red!)

• We learn:

  1. Patterns: circle, square, circle, square…

  2. Putting numbers in order: 1, 2, 3, 4…

  3. Understanding what comes before or after a number

• Helps us think better and solve simple problems!

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7. Using Algebra Skills in Daily Life (Early Algebra Thinking)

• Algebra means using a blank or a symbol to stand for a missing number.
  Example: 2 + ___ = 5 (Answer is 3!)

• We learn to:

  • Guess the missing number

  • Complete number sentences
    Example: 4 = ___ + 2 (Answer is 2!)

• It helps us think logically and carefully.

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8. Using Number and Time Relationships in Different Situations

• We use numbers to tell time:

  1. Clock – 1 o’clock, 2 o’clock, etc.

  2. Day – Today, tomorrow, yesterday

  3. Week – There are 7 days in a week

• Example:
  I wake up at 6 o’clock.
  We go to school from Monday to Friday.

• Helps us be on time and plan well.

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9. Using Number and Money Relationships in Daily Life

• We use money to:

  1. Buy things

  2. Count coins and notes

  3. Know if we get the correct change

• Example:
  An apple costs 200 shillings. I give 500. I get 300 back.

• Helps us:

  1. Save money

  2. Spend wisely

  3. Do simple shopping

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