- Slides: 30
E V K I T O C O A B R E E T T O N I N Y TH M A M B Y _ _ _ _ _ _ _ _ _ _
Welcome to Unit One – Place Value with addition and subtraction
Less than < Greater than> <>
Vocabulary • Greater than (>) – a symbol used to show numbers greater than another • Less than (<) – a symbol used to show numbers less than another • Equals (=) a symbol used to show numbers having the same value
HOW TO COMPARE USING >, < AND = Example 1: Compare 76 and 67 Write: Say: 67 < 76 67 is less than 76 76 > 67 76 is greater than 67 Remember, the mouth of the symbol (> or <) always opens to the greater number.
How to compare numbers 1 2 3 If numbers Compare at are the same Line up the highest numbers place value go to next digit to the right 12, 391 8, 971 13, 762
Rounding Finding an approximate number that has fewer non-zero digits, so that it will be easier for further estimation calculations. Usually, numbers are rounded to the nearest ones, tens, hundreds, etc.
The Rounding Rap Find the place value and underline the digit, Move to the right and circle it, get it? Zero through four – stays the same, Five through nine – Add one is the game. Now flex your muscles like a hero. Digits to the right change to zero. All other digits stay the same. Yo!! You’re a winner in the rounding game! Remember in rounding the high 5 is KEY!
Rounding to the nearest 10 26 rounded to the nearest 10 Think it through: 26 is between 20 and 30 on a number line 25 is halfway I must round to the higher number 30 Rounding to the nearest 100 347 rounded to the nearest 100 Think it through: 347 is between which two hundreds 300 and 400 350 would be halfway 347 is less than halfway round down to 300
Rounding to any place Ex. 67, 589 rounded to the nearest thousand Think it through with steps… Find the place value to round to That is the 7 underline it Now go to the right if the number is 5 or higher and one to the underlined place change everything else to zero 68, 000. CHECK – by saying 67, 589 is between 67, 000 and 68, 000
If the number to the right is 4 or lower keep the underlined number the same and change the other numbers to the right to zeros. Ex. 67, 389 rounded to the nearest thousand 3 is four or less so keep the 7 and change the rest of the numbers to the right to zeros. 67, 000. CHECK – by saying 67, 389 is between 67, 000 and 68, 000
Addition Words: • Sum *Total *Plus • Altogether *and • Increased by • Together *combined
Subtraction Words difference left over less than Exceed minus are not take away remain fewer how many more