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Read the following:

1. I, V, X, L, C, D, M.

2. II, VI, XIII, XXV, XXXI, DC.

3. IV, IX, XL, XC, CD.

4. VII, XII, XXII, XXXV, XLI.

5. LVII, LXIII, LXXVI, LXXXI.

6. VIII, XIX, XXIX, XXXIII, LXXXVIII.

Write the following in the Roman notation: 1. 20, 30, 40, 50, 60, 70, 80, 90, 100.

2. 21, 32, 45, 56, 67, 78, 83.

3. 4, 9, 400, 900.

4. 19, 59, 89, 490.

5. 24, 36, 99.

6. 100, 500, 1,000, 1,500, 1,800, 1,900, 1,909.

7. The numbers 1 to 20 inclusive.

8. 22, 36, 47, 59, 102, 98, 77.

Writing Dollars and Cents

How many cents in one dollar?

How many cents in one half-dollar?

How many cents in one quarter-dollar?

How many cents in one dime?

We may write one dollar in this way, $1. The sign $ means dollar.

Write 2 dollars; 3 dollars; 5 dollars.

We write one dollar and ten cents in this way, $1.10. Note that the dollars are separated from the cents by a The period is called the decimal point. 2 dollars and 50 cents.

dot or period. Write:

4 dollars and 75 cents.

8 dollars and 95 cents.

3 dollars and 5 cents.

10 dollars and 9 cents.

You have learned to write ten cents in this way, 10 ct. It may be written $.10. Six cents may be written, $.06.

Write 75 cents; 68 cents; 9 cents; 3 cents.

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Nineteen dollars and twenty cents.
Forty dollars and eleven cents.
Six dollars and twelve cents.
Eighteen dollars and fifty cents.
Sixty dollars and forty-six cents.
Eight dollars and four cents.
Seventeen dollars and sixteen cents.

Eleven dollars and forty cents.

Thirty dollars and thirty cents.

ADDITION

SIGHT EXERCISE

Addition by Decades

Add at sight and memorize :

1. Add 1 to each figure in the outer circle; add 2 to each figure; add 3, 4, 5, 6, 7, 8, 9.

2. Draw a diagram like the one in this exercise. Put the numbers 7, 17, 27, etc., in the outer circle.

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76 7

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6 5

66

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Add 1 to each number in the outer circle; add 2 to each number; add 3, 4, 5, 6, etc.

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1. How much money will you need to buy a sixcent book and a twelve-cent pencil box?

2. After there were 42 boys in our class, 3 new ones were admitted. How large was the class then?

3. Our teacher took some of the children to the Park: on Wednesday she took 8 boys and 10 girls; and on Friday, 6 boys and 4 girls. How many children did she take to the Park?

4. One boy picked 39 daisies and 20 buttercups. How many flowers did he pick?

Suggestions for Rapid Addition

1. In adding, do not count or repeat numbers. In example 1 and in all other column adding, say, 9, 13, 19, 27-not, 9 and 4 are 13; 13 and 6 are 19, etc. Prove your answer by adding in the opposite direction.

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2. A column of figures can be added more rapidly and more accurately by combining two or more of the figures that make 10.

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Notice that 7 and 310; 8 and 2 = 10; 6 and 4 10. Therefore you can add 10, 20, 30, 33. After you have added a few columns in this way, you will learn to see the 10's without marking the numbers that make 10.

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9. What is the sum of 64, 83, 23, 41, 79, 28,

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zines. Fill in the blanks with numbers of three orders, forming as many combinations of 10 as you

can.

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