LESSON III. Subtracting by Twos. TWO cents taken from 5 cents leave how many cents? SOLUTION.-Two cents taken from 5 cents leave 3 cents. 2. How many are 2 taken from 3? 2 from 4? 2 from 6? 2 from 8? 2 from 10? 3. How many are 2 taken from 5? 2 from 7? 2 from 9? 2 from 11? 2 from 12? 4. Mary had 5 oranges and gave 2 of them to Fanny; how many oranges had Mary left? SOLUTION.-Mary had left the difference between 5 oranges and 2 oranges, which is 3 oranges. 5. Willie had 6 marbles and lost 2 of them; how many marbles did Willie then have? 6. Eddie tried to spell 10 words and missed 2 of them; how many did he spell correctly? 7. Begin at 14 and count backward by 2's to two. Begin at 13 and count backward by 2's to one. NOTE.-Teach the pupils the use of - and, and have them write the subtraction table on the board, using these signs. One Hundred. Two Hundred. Three Hundred. Five Hundred. 200 300 500 100 NOTE.-The teacher will drill the pupil in reading and writing numbers from 100 to 500. LESSON IV. Adding by Threes. HOW many are 2 cents and 3 cents? SOLUTION.-2 cents and 3 cents are 5 cents. NOTE.-Use the numeral frame for these problems, if it is needed. 2. How many are 1 and 3? 3 and 3? 5 and 3? 2 and 3? 4 and 3? 6 and 3? 3. How many are 7 and 3? 9 and 3? 11 and 3? 8 and 3o 10 and 3? 12 and 3? 4. There are 5 roses on one bush, and 3 roses on another bush; how many roses on both bushes? 5. I gave 4 cents to John and 3 cents to James; how many cents did I give to both? 6. Edwin had 6 tame rabbits and caught 3 wild ones; how many did he then have? 7. Begin at 1 and count by 3's to 13; at 2 and count by 3's to 14; at 3 and count by 3's to 15. 2137 3108 | 23 31 32 46 28 65 73 12351 32161 EXERCISES. 3 3 23 64 13 23 23 213 230 30 30 21 132 133 52 64 43 723 625 NOTE.-Continue the drill in reading and writing numbers from 100 to 500. LESSON V. Subtracting by Threes. IF Emma has 5 bunches of grapes and eats 3 of them, how many bunches will remain? SOLUTION.-There will remain the difference between 5 bunches and 3 bunches, which is 2 bunches. 2. Three from 4 leaves how many? 3 from 6? 3 from 8? 3 from 5? 3 from 7? 3 from 9? 3. Three from 10 leaves how many? 3 from 12? 3 from 14? 3 from 13? 3 from 11? 3 from 15? 4. Mary had 6 cakes and gave her brother 3 cakes; how many cakes had Mary left? 5. Thomas had 8 marbles and lost 3 of them; how many marbles remained? 6. There were 9 birds on a tree and 3 flew away; how many birds remained? 7. Subtract by 3's from 15 to naught; from 14 to 2; from 13 to 1. 8. Write the subtraction table for threes on the slate or blackboard, using the signs — and =. From 365 743 569 984 872 731 474 Take 303 231 132 333 321 Six Hundred, Seven Hundred, Eight Hundred, One Thousand. 310 320 1000 LESSON VI. Adding by Fours. HOW many boys are 3 boys and 4 boys? SOLUTION.-Three boys and 4 boys are 7 boys. 2. How many are 1 and 4? 5 and 4? 4 and 4? 3 and 4? 6 and 4? 2 and 4? 3. How many are 7 and 4? 10 and 4? 8 and 4? 11 and 4? 9 and 4? 12 and 4? 4. If there are 3 boys on one bench and 4 boys on another bench, how many boys are there on both benches? 5. A man paid 5 dollars for a pig, and 4 dollars for a lamb; how much did he pay for both? 6. I gave 8 cents to a poor woman, and 4 cents to her little daughter; how much did I give both? 7. Write the addition table for fours on the blackboard or slate, using the signs + and =. 8. Add by 4's from 4 to 16; from 1 to 13; from 2 to 14; NOTE.-Drill in reading and writing numbers from 500 to 700. 34 432 104 32 231 333 33 21 424 501 62 302 400 LESSON VII. Subtracting by Fours. IF we take 4 books from a pile of 7 books, how many books are left? SOLUTION.-There are left the difference between 7 books and 4 books, which is 3 books. 2. Four from 6 leaves how many? 4 from 5? 4 from 8? 4 from 7? 4 from 9? 4 from 12? 3. Four from 13 leaves how many? 4 from 15? 4 from 10? 4 from 11? 4 from 16? 4 from 14? 4. Mary had 6 roses, and gave her mother 4 roses; how many roses did Mary keep? 5. Walter bought 10 apples, and ate 4 of them; how many apples then remained? 6. Twelve boys were playing ball, when 4 of them left; how many remained? 7. Write the subtraction table by fours, on the blackboard or on your slates, using the signs and . 8. Count backward by 4's, from 16 to zero; from 15 to 3; from 14 to 2; from 13 to 1. WRITTEN EXERCISES. From 6 7 5 8 9 4 10 12 15 16 13 11 14 Take 4 4 4 4 4 4 4 4 4 4 4 4 4 ཤ*།༞」 69 75 98 76 43 24 14 13 Take 41 34 43 22 NOTE.-The teacher will drill the pupil in reading and writing numbers from 500 to 800. |