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225-230. From each one of the numbers 49, 52, 65, 76, 82, 93 take first 12, and from the remainder take 15. In the same manner take 13 and 16; 14 and 17.

231-236. Similarly from 41, 58, 63, 74, 85, 97 take 11, and from the remainder take 18; also 16 and 19; also 12 and 17.

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Applications.—245. Mr. A has 400 sheep, Mr. B 200. How many has Mr. A more than Mr. B?

246. A clerk receives a salary of $1,200, and pays $290 for rent. How much remains for other expenses?

Note.—The sign $ is used to denote dollars. It is called the dollar mark. 247. Mr. Abel sold his house for $860. He had bought it for $730. How much did he gain?

248. If a boy resides 580 steps from the school-house, but, on going to school, stops on his way after taking 380 steps, how many has he yet to take?

249. A farmer bought a horse and two cows for $195. If one cow cost $49, and the other $50, how much did he pay for the

horse?

Units, Tens, and Higher Orders.

32. Case I. When no term of the subtrahend is greater than the term in the same order of the minuend.

Example.-From 796 subtract 354.

Illustration.-Suppose that Mr. Jones has seven sacks of money, each containing one hundred silver dollars, nine rolls of ten dollars each, and six dollars lying loose on his table, as represented in the following picture, and that Mr. Smith calls to collect 354

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dollars. The pupil will readily understand that Mr. Jones has only to give Mr. Smith four of the single pieces, five of the ten dollar rolls, and three of the sacks containing one hundred dollars each, and that he will then have 442 dollars remaining.

Note. The learner should practice himself in such illustrations till he is familiar with them. He will thus surely learn the significance of the processes of

arithmetic.

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In the same way, tell how you would take 325 from 697 buttons, supposing that you had 6 cards having 100 buttons sewed on to each, 9 cards with 10 buttons on each, and 7 loose buttons. Show how the remainder would be found by work on the slate.

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19-32. From 879 take 213, 425, 263, 34, 728, 658, 870, 457, 23, 43, 654, 222, 333, 400.

33-46. Take 432 from each of the following numbers: 543, 733, 645, 987, 655, 438, 679, 542, 632, 777, 989, 656, 686, 567.

4

Note. In the process of subtraction there are two modes of reckoning. For instance, in subtracting 5 from 9, some say, “5 from 9 leaves 4"; others, “5 and 4 are 9"; both writing the 4 as it is spoken, or better, as it comes into the mind. The results are the same, but the latter wording is recommended in practice for many reasons, one of which is that it is less liable to error. It should not be introduced, however, till the former is well understood by the learner.

Example. From 789 subtract 435.

789

435

354

Wording.-5 and 4 are 9, 3 and 5 are 8, 4 and 3 are 7. Only the results printed in heavy type should be spoken, and these should be written as uttered.

This is called the "making up method." Besides being less liable to error, other advantages will be seen in Case II. See Ex. 68, p. 44, also Shorter Method in Long Division, p. 90.

33. Case II. When any term of the subtrahend is greater than the term in the same order of the minuend.

Example. From 442 subtract 136.

Illustration. After Mr. Jones had paid Mr. Smith, he had $442 left, out of which he is paying Mr. Brown $136. But since he has only two loose dollars, he is here represented as having

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taken ten dollars from one of the rolls, and put them with the two, thus making twelve single pieces. From these he has put forward six pieces. He has shoved forward also the three remaining ten dollar rolls, and one sack containing a hundred dollars. dollars left.

Thus he has

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Note. The pupil does not understand the foregoing illustrations if he can not go farther and explain the case, where he has to "borrow," both from the tens and from the hundreds; or, where there are no tens, perhaps also no units.

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67. Explain how you could most conveniently take 585 pencils from the number of pencils represented above.

68. In the same way explain how you would proceed to take 378 match-sticks from the number represented below.

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