ADDITIONS AND SUBTRACTIONS UP TO 9

When you add a book in a backpack, you use the addition operation. And when you take a pen from your pencil case, you use the subtraction operation.

Discover how additions and subtractions work with numbers from 0 to 9. Learn how to use these two operations!

Notes

ADDING AND SUBTRACTING... LET'S DISCOVER THE FUNDAMENTAL OPERATIONS! 

LET'S START WITH THE FINGER-COUNTING.

Learn FREE with videos and interactive exercises

ADDITION

 

ALBERT HAS 3 EYES. LISA HAS 2 EYES. HOW MANY EYES DO THEY HAVE TOGETHER?

THEY HAVE, IN TOTAL, 5 EYES. WE DID AN ADDITION: 3 + 2 = 5

THE ADDITION SYMBOL IS  £$ + $£ THAT IS THE PLUS SIGN. IT ALLOWS US TO ADD TWO OR MORE NUMBERS.

HOW MANY EYES DO ALBERT, LISA AND RITA HAVE?

ADDITION ON A NUMBER LINE

LET'S USE THE NUMBER LINE TO FIND OUT WHAT 4 + 5 EQUALS.

RITA STARTS AT 4 AND JUMPS 5 TIMES ALONG THE NUMBER LINE. WHERE IS SHE ON THE NUMBER LINE?

4 + 5 = 9

FOUR PLUS FIVE EQUALS NINE. RITA ARRIVES ON NUMBER 9.

IF RITA STARTS AT 1 AND JUMPS 6 TIMES, WHERE IS RITA NOW?

SUBTRACTION

 

OSCAR HAS 2 EYES. IF HE CLOSES ONE EYE, HOW MANY EYES ARE OPEN?

JUST ONE! WE DID A SUBTRACTION: 2 – 1 = 1

AND WE READ IT: TWO MINUS ONE EQUALS ONE.

THE SUBTRACTION SYMBOL IS £$ - $£ THAT IS THE MINUS SIGN. IT ALLOWS US TO SUBTRACT NUMBERS.

HOW MANY EYES ARE OPEN IF BOTH ALBERT AND OSCAR CLOSE ONE EYE?

SUBTRACTION ON A NUMBER LINE

 

LET'S USE THE NUMBER LINE TO FIND OUT WHAT 6 – 4 EQUALS.

RITA STARTS AT 6 AND JUMPS 4 TIMES TO THE LEFT ALONG THE NUMBER LINE. SHE IS STANDING ON NUMBER 2. 6 – 4 = 2

SIX MINUS FOUR EQUALS TWO.

PAY ATTENTION! WE CAN DO A SUBTRACTION OPERATION ONLY IF THE FIRST NUMBER IS BIGGER THAN THE SECOND ONE.

IF RITA STARTS AT 9 AND JUMPS 5 TIMES TO THE LEFT, WHERE IS RITA ON THE NUMBER LINE?