91Ó°ÊÓ

How many two-digit whole numbers are there?

For the following problems, complete the table by rounding each number to the indicated positions. 388,551 $$ \begin{array}{|l|l|l|l|} \hline \text { hundred } & \text { thousand } & \text { ten thousand } & \text { million } \\ \hline & & & \\ \hline \end{array} $$

For the following problems, show that the pairs of quantities yield the same sum. $$(80+52)+6 \text { and } 80+(52+6)$$

For the following problems, perform the additions. If you can, check each sum with a calculator. $$ \begin{array}{r} 16,515 \\ +42,223 \\ \hline \end{array} $$

For the following problems, perform the subtractions. You may chedk each difference with a calculator. $$ \begin{array}{r} 15 \\ -8 \\ \hline \end{array} $$

For the following problems, perform the additions. If you can, check each sum with a calculator. $$616,702+101,161$$

How many three-digit whole numbers are there?

For the following problems, show that the pairs of quantities yield the same sum. $$(114+226)+108 \text { and } 114+(226+108)$$

For the following problems, perform the subtractions. You may chedk each difference with a calculator. $$ \begin{array}{r} 19 \\ -8 \\ \hline \end{array} $$

For the following problems, complete the table by rounding each number to the indicated positions. 4,752 $$ \begin{array}{|l|l|l|l|} \hline \text { hundred } & \text { thousand } & \text { ten thousand } & \text { million } \\ \hline & & & \\ \hline \end{array} $$