NEW WORK CARRYING CARRYING IN ADDING LARGER NUMBERS 83 67. How to Add Larger Numbers. (CLASS WORK.) You have learned much about adding, but there are other things you ought to know. All but one of the following examples should be easy for you. Without using your pencil, get ready to give the answers to them. Which example is the hard one? Most pupils think it is Example 6. This is the way to find the answer: 47¢ 28¢ 75¢ 7. 27¢ 8¢ and 7¢ are 15¢. the 5 under the 8. 15¢ is 5 cents and 1 dime. Write Then add the 1 dime to 2 and 4. The sum of 1 and 2 is 3. 3 and 4 are 7. Write the 7 in the dimes' column. What is the answer? Can you give the answer to Example 7? Use pencil 38¢ and paper if you need to. 8. 29¢ 17¢ 38¢ You may need some help on Example 8. 8¢ and 7¢ are 15¢. 15¢ and 9¢ are 24¢. 24¢ is 4 cents and 2 dimes. Write the 4 under the cents' column. Then add 2 dimes to the 3 and 1 and 2. Write the sum under 3 in the dimes' column. What is the answer? Look at Example 6 again. How many dimes did you add to the dimes' column? In Example 8 how many dimes did you add to the dimes' column? When you add a number to another column, you carry the number to that column. In all addition problems you must remember what you are adding, or your answers won't be right. Since you are adding papers, the answer to this example is 62 papers. "Papers" is the name of this answer. Be sure that you always give the right name to your answer. Look at Examples (A), (B), (C), and (D) on page 85. 11. What number is carried in Example (A)? 12. What number is carried in Example (B)? In (C)? In (D)? You have now learned to carry in addition. Remember that you sometimes carry 1, sometimes 2, other times 3, or Sometimes you carry nothing. even more. (ORAL 68. Practice in Finding What Is Carried. AND WRITTEN WORK.) Without using your pencil, first tell what number you would carry in these examples. Then copy the examples and find the answers. NEW WORK PROBLEM ANALYSIS* 69. How to Get Answers to Problems. (CLASS WORK.) Sometimes children who can add and subtract very well have trouble in getting the answers to problems, because they do not know when to add and when to subtract. This lesson will give you some help in getting the answers to problems. Read the first problem at least twice and then answer the questions about it. Problem 1. Jane had 16 cents. Her father gave her 10 cents more. How much did Jane then have? 1. What does this problem ask you to find? 2. Must you add or subtract to get the answer? 3. What is the answer? Sometimes a problem will ask you to find more than one answer. Look at Problem 2 below. Problem 2. Tom's toy boat cost 45 cents. Will's toy boat cost 32 cents. (a) What did both boats cost? (b) How much more did Tom's boat cost than Will's? 1. What does part (a) of this problem ask you to find? 2. Will you add or subtract to answer (a)? 3. What is the answer to (a)? 4. What does question (b) of the problem ask for? 5. Must you add or subtract in (b)? 6. What is the answer to question (b)? *TO THE TEACHER: See Teacher's Note 8. |