Rounding is a maths strategy that simplifies the numbers in a problem by converting the digits to the closest one, ten, hundred etc. Addition is the process of adding a number to another number. Division is the process of sharing an amount of something equally.
If a digit is within 0-4, the number should round down. If a digit is 5-9, the number should round up. If rounding to one decimal for example, 21.76. The last decimal digit in this number is '6'. Six is more than five, so 76 rounds up to 8 which represents 80. The number would become 21.8.
Adding decimal numbers is similar to normal addition. For example, 9.23 + 2.54. People should start by adding the last decimals. 0.03 + 0.04= 0.07. Then the tens decimal, 0.20 + 0.50= 0.70. 0.70 + 0.07= 0.77. After that the wholes are added, 9 + 2= 11. The total becomes 11.77. However, if the decimal total equals over than 100, it becomes a whole. So a number such as 0.154 would become 1.54.
Dividing a decimal number can also be the same as dividing a whole number. For example, 75.30 divided by 5. People should start by dividing 75 by five to make 15, because 15 x 5= 75. Then, 30 divided by five is 6, because 6 x 5= 30.
LI: to investigate the units of time.
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