LESSON XLVIII. 1. What principal, in 4 years, at 5 per cent., will amount to $96? NOTE. — The interest of any sum of money at 5 per cent., for 4 years, isor of the principal; then the amount is of the principal, for the amount is of the principal, plus the interest,; then, since of the principal = $96, the principal: of $96 = $80. = 2. What is the present worth of $96, due 4 years hence, at 5 per cent.? NOTE. The present worth of a sum due at some future time is what should be paid now, instead of paying that sum then; it is, therefore, equivalent to a principal which, being put at interest, will amount to the debt at the time of its becoming due. 3. What is the present worth of $50, due in 5 years, at 5 per cent.? NOTE. That is, what principal, put at interest for 5 years, at 5 per cent., will amount to $50? 4. What is the present worth of $136, due in 6 years, at 6 per cent.? 5. What is the present worth of $172, due in 9 years, at 8 per cent. ? 6. What is the present worth of $74, due in 5 years, at 10 per cent.? 7. What is the present worth of $78, due in 1 year, at 4 per cent. ? 8. What is the present worth of $85, due in 10 years, at 7 per cent.? 9. What is the present worth of $96, due in 8 years, at 7 per cent.? 10. What is the discount on $100, due in 5 years, at 5 per cent.? 8. What is the interest of $60 for 7 years, at 6 per cent.? For 9 years? 9. What is the interest of $1 for 1 year, at 6 per cent.? At 7 per cent. ? At 5 per cent. ? 10. What is the interest of $10 for 1 year, at 6 per cent.? At 7 per cent.? At 5 per cent.? 11. What is the interest of $100 for 1 year, at 6 per cent.? At 7 per cent.? At 5 per cent.? 12. What is the interest of $100 for 5 years, at 7 per cent.? For 6 years? For 7 years? 13. What is the interest of $150 for 2 years, 7 per cent. For 3 years? at 14. What is the interest of $106 for 3 years, at 7 per cent.? At 8 per cent.? 15. What is the interest of $320 for 4 years, at 10 per cent.? At 12 per cent.? 7 16. What is the interest of $415 for 5 years, at per cent.? Of $540? 17. What is the interest of $100 for 1 month, at 6 per cent.? NOTE. Since the interest of $100 for 1 year, at 6 per cent., = $6, the interest for 1 month, or of a year, 11⁄2 of $6= $12-$150 cents. = = = 18. What is the interest of $10 for 1 month, at 6 per cent.? Of $1? Of $6? 19. What is the interest of $60 for 2 months, at 6 per cent.? Of $9? Of $90 ? 20. What is the interest of $200 for 1 month, at 6 per cent.? Of $300? Of $370? Of $420? Of $426? 21. What is the interest of $100 for 4 months, at 6 per cent.? For 5 months? For 6 months? For 8 months? For 10 months? 22. What is at 7 per cent.? 23. What is the interest of $100 for 6 months, At 8 per cent. ? the interest of $100 for 4 years and 4 months, at 6 per cent.? Of $200? Of $300? Of $50? Of $350 ? 24. What is the interest of $50 for 4 years and 6 months, at 7 per cent.? 25. What is the interest of $150 for 6 years and 7 months, at 6 per cent. ? 26. What is the interest of $460 for 3 years and 2 months, at 5 per cent. ? 27. What is the interest of $625 for 5 years and 3 months, at 7 per cent.? LESSON XLIV. 1. What is the interest of $100 for 1 day, at 6 per cent.? For 6 days? For 15 days? = 30 NOTE. In reckoning interest, it is customary to call 30 days a month. Hence, 1 day of a month; 6 days= 3 of a month; 15 = 1 of a month, and so on. Since the interest of $100 for 1 month is 50 cents, for go of = a of 50 cents 13 cents; for of a month it is = 10 cents, and for of a month it is of 50 cents: month it is of 50 cents = 25 cents. 2. What is the interest of $1 for 30 days, at 6 per cent.? For 60 days? For 120 days? For 20 days? For 40 days? 3. What is the interest of $20 for 5 days, at 6 per cent.? For 12 days? For 15 days? 4. What is the interest of $50 for 21 days, at 7 per cent.? For 24 days? For 45 days? 5. What is the interest of $40 for 4 years, at 6 per cent.? For 4 months? For 4 years and 4 months? For 20 days? For 4 years, 4 months and 20 days? 6. What is the interest of $400 for 6 years, 2 months and 10 days, at 2 per cent.? 7. What is the interest of $100 for 4 months and 15 days, at 7 per cent.? 8. What is the interest of $125 for 4 years, 2 months and 10 days, at 7 per cent.? 9. What is the interest of $120 for 3 years, 4 months and 10 days, at 6 per cent.? 10. What is the interest of $140 for 1 year and 20 days, at 6 per cent.? 5 11. What is the interest of $30 for 6 years, at per cent.? At 7 per cent.? 12. What is the interest of $10 for 4 years and 3 months, at 7 per cent.? At 8 per cent.? 13. What is the interest of $150 for 5 years and 4 months, at 6 per cent.? 14. What is the interest of $320 for 2 years, 4 months and 20 days, at 6 per cent.? 15. What is the interest of $45 for 4 years, 8 months and 16 days, at 6 per cent.? 16. What is the interest of $80 for 6 years, 6 months and 12 days, at 6 per cent.? 17. Required the interest of $126 for 3 years, 6 months and 20 days, at 6 per cent. 18. Required the interest of $175 for 4 years, 4 months and 18 days, at 6 per cent. 19. Find the interest of $210 for 3 years and 4 months, at 7 per cent. NOTE. - In reckoning interest at 4, 5, 7, or 8 per cent., it is often most convenient to find the interest at 6 per cent., and then change it to the given per cent. The interest at 4 per cent. is equal to that at 6 per cent. less of itself; 5 per cent. is 6 per cent. less of itself; 7 per cent. is 6 per cent. with added; and 8 per cent. is 6 per cent. with added. 20. Find the interest of $42 for 3 years and 2 months, at 6 per cent. At 4 per cent. per cent. At 7 per cent. 21. Find the interest months and 12 days, at cent. At 5 per cent. per cent. At 8 per cent. At 7 per cent. At 5 years, 8 At 4 per 22. What is the interest of $160 for 3 years, 4 months and 9 days, at 6 per cent.? At 5 per cent.? At 8 per cent.? At 7 per cent.? 23. What is the interest of $200 for 2 years, 6 months and 15 days, at 4 per cent.? At 6 per cent.? 24. The interest of $240 for a certain time is $18, at 6 per cent.; how much is it at 8 per cent.? 25. The interest of $225 for 4 years is $54; what is the interest for 1 year? For 3 months? For 2 months? For 1 month? 26. The interest of $120 for 1 year is $7.20; how much is it for 4 months? For 2 months? For 1 month and 10 days? For 20 days? LESSON XLV. 1. What is the amount of $40 for 2 years, at 6 per cent.? NOTE. The amount is the sum at interest, or the principal, and the interest taken together. The interest on $40 for 2 years, at 6 per cent.= $4.80; and $40+$4.80=$44.80, the amount. 2. What is the amount of $60 for 4 years, at 4 per cent.? 3. What is the amount of $80 for 3 years, at 5 per cent.? 4 4. What is the amount of $100 for 6 years, at cent. ? per 5. What is the interest of $70 for 6 years, at 7 per cent.? 6. What is the amount of $125 for 2 years, 7 per cent.? at 7. What is the interest of $100 for 3 years and 4 months, at 7 per cent.? 8. What is the interest of $25 for 6 years and 1 month, at 6 per cent.? |