Express as common fractions in lowest terms: 1. a. 5 tenths b. 50 hundredths c. 500 thousandths 2. a. 2 tenths b. 20 hundredths Sight Exercises 1. Compare the following sets: c. 200 thousandths a. .5, .50, and .500 b. .3, .30, and .300 c. .4, .40, and .400 2. What is the effect of writing one or more ciphers at the right of a decimal? 3. Compare the following sets: 4. What is the effect of prefixing (a) one decimal cipher? (b) Two decimal ciphers? Adding and Subtracting Decimals 5. (a) B is 5.04 miles east of A. C is 4.26 miles east of B. How many miles is C from A? (b) C is 9.3 miles east of A. B is 5.04 miles east of A. How far is it from B to C? A 9.3 mi. -C 5.04 mi. B 4.26 mi. 1. A mark is worth $.238 and a franc is worth $.193. What is the total value of the two coins? 2. Add the following: a. 3.47 + .375 + 2.5 + 46.05 + 11.7 + 8.18 b. 12.25 +5.76+ 83.64 + 4.068 + 18.235 3. Find the difference in our money between the value of a mark and that of a franc. Multiplying Decimals Preparatory Exercises 1. Multiply by 3: a. 1 tenth. b. c. 13 thousandths. d. 1 and 1 tenth. dredths. f. 4 and 7 thousandths. 2. Give products: 11 hundredths. e. 2 and 3 hun In the product of two decimals, point off as many decimal places as there are decimal places in the multiplier and the multiplicand together. Written Exercises 1. How far will a train travel in 6.4 hours at the rate of 32.15 miles per hour? NOTE. In multiplying decimals, as in all other arithmetical operations, examine the reasonableness of the answer. A pupil that notes that 6 times 32 is nearly 200 will not write the answer as 20.576 or 2057.6. 2. Find products: a. 3.508 x 8 b. 3508 × 8.1 e. 2.345x7 f. 2345 x 7.2 i. 4.062 x 9 j. 4003 × 9.7 c. 35.08 x 8.3 d. 3.508 x 85 2.345 × 74 h. 7. 4.066 × 96 Division - Decimal in Quotient Written Exercises 1. (a) At $125 per acre, how many acres of land will cost $10,507? (b) How many cords of wood, at 128 cubic feet to the cord, are there in a pile of wood containing 720 cubic feet? Place a decimal point in the quotient when it is reached in performing the division, and continue the latter, annexing decimal ciphers to the partial dividends as may be required. Test by multiplying the quotient by the divisor. Sight or Written Exercises 1. Express in lowest terms: Sight or Written Exercises 1. Change to a decimal. a. 25 6. 125 c. 17 d. 23 125 e. 127 f. 118 3. Express as a common fraction in lowest terms: a. .036 b. .135 c. .027 PROCESS a. .036=1880=280. Ans. c. .027=127. Ans. Write each in the form of a common fraction and reduce to lowest terms by dividing the numerator and the denominator by the same number; 2, 4, 8; 5, 25, 125. NOTE. A fraction having 10, 100, or 1000 for its denominator can be reduced to lower terms only when its numerator is either an even number, or terminates in 5. 4. Change to common fractions in lowest terms: a. .062 b. .065 c. .068 d. .064 e. .069 f. .008 g. .012 h. .015 i. .024 j. .025 k. .123 7. .234 5. Express as the fraction of a dollar: |