Today we will round very large and very

Today we will round very large and very small numbers. round – to replace a number by another number of approximately the same value but having fewer digits: To the nearest dollar, the rounding of $27. 68 yields $28. very large numbers – numbers in the millions or higher; have 7 or more digits very small numbers - numbers in the thousandths or smaller; thousandths are fractional parts of 1000 Concept

Molly has $16 in her pocket She buys: • 3 hotdogs @ $1. 89 each • 3 milkshakes @ $2. 19 each • 3 Large French fries @ $ $1. 79 each Does she have enough money?

rounding to replace a number by another number of approximately the same value but having fewer digits TPS APK

very large numbers Numbers greater than 1 million 1, 000 457, 923, 493 10, 000, 000 TPS APK

very small numbers less than 1. They are represented by numbers to the RIGHT of the decimal point. They are also called decimals. . 5 5 tenths. 075 75 thousandths TPS APK

decimal a number less than 1. It is represented by numbers to the RIGHT of the decimal point. . 5 5 tenths. 75 75 hundredths APK

When To Round When the question asks: – “Estimate how many…” – “About how many…” – Can you think of anymore?

Why is it important that we can round very large and very small numbers? §When we are asked for an estimate, this will help us figure out the answer quicker! § Estimating is a great way to eliminate wrong answer choices § What are other reasons why it is important to know how to estimate very large and very small numbers? IMP

Let’s test the poem! The rounding poem Find your number Look right next door 4 or less, just ignore 5 or more add one more!

Rounding Whole Numbers Round 474, 000 to the closest hundred millions. Find your number Look right next door Four or less, just ignore 474, 000 Five or more, add one more

474, 000 Rounded to the hundred millions becomes 500, 000 Round 474, 000 to the closest 10 million’s 474, 400, 000 Just ignore – 470, 000

What about decimal numbers The same rules (and poem) apply! Round 4. 167 to the closest hundredths 4. 167 Find your number 4. 17 Look right next door

Remember If you are asked to round to the nearest tenth……. your answer stops at the tenth place! Example: Round 42. 73 to the closest tenth would be 42. 7

Special Case! Rounding a 9 Round 2. 197 to the closes hundredths Since there is a “ 9” in the hundredths place consider the tenth and hundredths together – 19 – do you leave it at 19 or move it to 20?

Round 4. 95 to the closest tenth Since there is a “ 9” in the tenth spot consider the ones and tenths together…… should you leave it at 49 or move it to 50? 4. 95 rounded to the nearest tenth is 5. 0

Let’s work some problems out together! Steps 1. Find your number 2. Look right next door 3. 4 or less, just ignore 4. 5 or more add one more! 125, 345, 878 125, 346, 000 987, 565, 484 987, 565, 000 125, 345, 878 125, 350, 000 987, 565, 484 987, 570, 000 125, 345, 878 125, 000 125, 345, 878 100, 000 987, 565, 484 988, 000 987, 565, 484 10, 000

Let’s work some problems out together! Steps 1. Find your number 2. Look right next door 3. 4 or less, just ignore 4. 5 or more add one more! 125. 0238 125. 0 987. 9655 988. 0 125. 0238 125. 02 987. 9655 987. 97 125. 0238 125. 024 987. 9655 987. 966

Let’s review! • What does Rounding mean? • What are very large numbers? Numbers in the millions or billions. Numbers like 2, 304, 000 and 2, 455, 098 What are very small numbers? Numbers smaller than one. Numbers like 0. 456 and 0. 4 Closure