# A Mental Arithmetic on the Inductive Plan ...

R.S. Davis & Company, 1875

### Contents

 Section 1 1 Section 2 4 Section 3 26 Section 4 28 Section 5 42 Section 6 53 Section 7 60 Section 8 67
 Section 12 107 Section 13 128 Section 14 133 Section 15 141 Section 16 159 Section 17 160 Section 18 162 Section 19 167

 Section 9 78 Section 10 93 Section 11 99
 Section 20 177 Section 21 179 Section 22 180

### Popular passages

Page 21 - Multiplication is the process of taking one number as many times as there are units in another number.
Page 74 - Multiplying the numerator and denominator of a fraction by the same number does not alter the value of the fraction.
Page 130 - If 2 men start from the same place and travel in opposite directions, one at the rate of 4 miles an hour, and the other at the rate of 5 miles an hour, how far apart will they be at the end of 1 hour ? At the end of 2 hours ? 5 hours?
Page 132 - Three men, A, B and C, are to share \$400 in the proportion of J, £ and ^ respectively ; but, as C died, it is required to divide the whole sum properly between the other two ; how much should each receive ? 20.
Page 26 - The Dividend is the number to be divided. The Divisor is the number by which we divide.
Page 112 - Interest is money paid for the use of money. The Principal is the sum of money which is loaned.
Page 28 - If 4% bonds to the amount of \$8000 face value are bought at 92^%, find the cost of the bonds, and the rate of income on the investment. 12. If 3 men can do a piece of work in 8 days of 10 hours each, how many men will be required to do the same work in 6 days of 8 hours each ? (Solve by proportion.) 13. By selling a horse for \$144, a profit of 60 per cent is made; find the cost of the horse.
Page 131 - A cistern has 4 pipes ; the first will fill it in 2 hours, the second will fill it 3 hours, the third in 4 hours, and the fourth will empty it in 2 hours ; now, if the pipes are all open at the same time, how long will it take to fill the cistern ? 10.
Page 87 - ... 291. MAGNITUDES WHICH ARE INVERSELY PROPORTIONAL TO OTHER MAGNITUDES OR TO THE SQUARES OF OTHER MAGNITUDES. EXAMPLE. If 5 men do a piece of work in 16 days, how long will it take 8 men to do a similar piece of work ? OPERATION AND EXPLANATION. It is evident that the time required will be inversely proportional to the number of men employed ; that is, if twice as many men are employed, not twice as much, but \$ as much time will be required.
Page 44 - TABLE. 4 farthings (qrs.) make 1 penny, marked d. 12 pence - - - - 1 shilling, - - s. 20 shillings - - - - 1 pound, - - £. Note.