ANSWERS TO PROBLEMS 255 



520. 1.1. 521. 0.93; 0.67; 0.53. 522. 280pounds. 523. 2/15; 2/15. 

 526. 30 inches. 528. 100 pounds. 529. 100 pounds. 530. 200 

 pounds. 531. 1| miles per hour; 2.5 miles per hour; 3| miles per 

 hour. 532. 133 pounds; 83 pounds. 533. lj miles per hour. 

 535 6f per day; 6 per day; 10 per day. 536. 200. 537. 89. 

 538 100 pounds. 539. 200 pounds. 540. 300 pounds. 541. 150 

 pounds. 542. 200 pounds. 543. 200 pounds. 545. 5.04 pounds. 

 546. 6.47 pounds. 547. 3 horsepower. 548. 4,500 pounds. 

 549. 3.85 pounds. 550. 2.8 miles per hour. 551. 40; 48 hours or 

 4.8 days. 552. 2f. 553. 2fc. 554. 1.78 (i. e. two are more than 

 sufficient). 555. 3.59 pounds. 556. 4.22 pounds. 557. 3,500 

 pounds. 558. 1,100 pounds. 559. 121; 22. 560. 121; 22. 561.3. 

 562. 18. 566. 3. 567. 266. 568. 88. 569. 2.84 (i. e. three will 

 do it easily). 570. 2. 571. 10.1; 139; 173; 282; 253; 374. 572. 

 29%. 573. 3.8%. 574. 58%. 575. 48%. 576. 74.3%. 

 577. 150 pounds; 46.1. 578. 200 pounds; 279 pounds; 498 pounds; 

 755 pounds. 579. High 29 pounds, low 3 pounds; High 22%, 

 low 2%. 580. 1J miles per hour; 1 mile per hour. 581. 23. 

 582. 36. 583. 937 pounds; 1,351 pounds. 584. 1$ miles per hour; 

 | mile per hour. 585. 22.4. 586. 1.22. 588. 28 pounds; 49 pounds; 

 21.5; 20.9. 589. 15.7; 8.4. 590. 6.4; 4.1. 591.2,550. 592.2,140. 

 594. 1 to 30; 1 to 16. 595. 52.8 feet; 12 feet. 596. 3.1; 1; 8.3. 

 597. 24 feet; 500 feet. 599. 500 pounds; 100 pounds (i. e. the 

 team or the brakes must hold back with a force of 100 pounds). 

 600. 235 pounds; 125 pounds; 640 pounds; 440 pounds. 601. 

 6; 300 pounds. 602. 2 miles per hour; 1.4 miles per hour (weight 

 of horses not included, otherwise 1.1 miles per hour). The rule 

 gives over 6 miles per hour which, of course, is too high; As fast 

 as safety will permit. 603. More than one-half of the time. 

 604. 9.4; 3 to 32 or about 1 to 11. 



CHAPTER XI 



606. 144. 607. 5; 4; 8; 15. 609. 32; 21.3; 60. 610. 43; 9; 98. 

 611. 216; 128; 756; 528; 900; 160; 213; 160. 612. 3,061. 613 

 $137.75. 614. 3,490. 615. $97.72. 616. 5,712. 617. $171.36. 

 618. $109.50. 619. $25.50. 620. $222.50. 621. $553.61. 622. 

 7,840. 623. 900; 1,200. 624. 11,520. 626. 12.600 at 800 per 

 square. 627. 19,000 at 800 per square. 628. 9 feet; f. 630. 20. 

 631. 113. 632. 3i. 633. 1|. 634. If. 635. 783. 636. 47. 

 637. 41. 638. 695. 639. 24|. 640. 10. 641. 8|. 



CHAPTER XII 



642. $30.00; $15.00. 643. $37.50. 644. $38.00; $121.60; $319.20. 

 645. $324.00; $518.00; $4,147.20. 646. 5 cents; $2.50; $8.00; 

 $1,152.00. 647. 83i 648. $365,000,000. 649. 8,726. 650. 

 $69,800. 651. 7,300. 652. 7 tons. 653. 28. 654. 122|. 



