Students should use their prior knowledge from first grade regarding 10 more or 10 less to understand that adding 10 to a number increases the digit in the tens place by 1 and subtracting 10 to a number decreases the digit in the tens place by 1. Students can then apply this to adding and subtracting 100 and the increase or decrease in the digit in the hundreds place by 1. Students should be able to add or subtract 10 or 100 mentally to or from any given number up to 1,200.
Read the following word problems. You may need paper and pencil to solve each problem.a) David is reading a really exciting book. He is on page 98. If he reads 10 pages every day, on what page will he be in 3 days? Draw a picture and explain your thinking.b) There were 815 jars of baby food stacked at the grocery store. Someone ran into the stack with their cart and some of the jars fell off the stack. There are 715 jars left in the stack. How many jars fell on the floor? Draw a picture and explain your thinking.
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2.7 Algebraic reasoning. The student applies mathematical process standards to identify and apply number patterns within properties of numbers and operations in order to describe relationships. The student is expected to: