1. Date: _____________Math 9/9H Place Value Which position is a digit of a number occupying? E.g.: 1 975 462.328 1 is in the millions place 9 is in the hundred thousands place 7 is in the ten thousands place 5 is in the thousands place 4 is in the hundreds place 6 is in the tens place 2 is in the ones place 3 is in the tenths place 2 is in the hundredths place 8 is in the thousandths place

2. Date: _____________Math 9/9H Rounding Rules 1.ONLY ROUND THE ANSWER (do NOT round steps!) 2.Only two choices: leave the number the same (if the following digit is less than five) Round the number up (if the following digit is five or greater) 3.Only round ONE digit in any number E.g.: round 75.6 to the nearest whole number (nearest “one”) This number could become 75 OR 76 To solve: look at the number to the RIGHT of the “ones” place

3. Date: _____________Math 9/9H To solve, look at the number to the RIGHT of the “ones” place: if that number is less than five, leave the answer as 75; if that number is 5 or greater, round the answer up to 76. So the correct answer is: 76! Examples to try: Round 43.672 to the nearest TENTH 43.7 Round 0.434 to the nearest HUNDREDTH 0. 43 Round 12 346 to the nearest HUNDRED 12 300 Round 869 942 to the nearest TEN THOUSAND 870 000

4. Date: _____________Math 9/9H Estimating Use rounding on all terms to make an educated guess of the answer E.g.: 47 x 104 -> round to 50 x 100 ~ 5000 actual answer: 4888 Do the “actual calculation” to check if your estimate is close Estimating is useful when checking if you answer seems “reasonable” E.g.: 89 x 201 -> round to 90 x 200 ~ 18 000 if your answer came to 1780, you would be suspicious you have made an error actual answer: 17 889

5. Date: _____________Math 9/9H Definitions Sum: the answer when you are adding Difference: the answer when you are subtracting Product: the answer when you are multiplying Factors: the things you multiply to get the product Quotient: the answer when you are dividing Divisor: the number you are “dividing by” (bottom number of a fraction) Dividend: the number you are “dividing into” (top number of a fraction)