11. £50{(1·05)3 + (1·05)2 + (1·05)} = £165. 10s. 13d.

7. 33.1, 3.236. 8. £2. 16s. 01d., he lost 123 per cent.

9. 12. 10., 6s., 04895.

12. £29. 6s. 7 d., £0. 9s. 81d. 14. £002, 34-3168.

16. £518, £1148, £1213. 19. 4s. 7·4d. per ounce.

11. 0, 4, 2500, 17.
13. £8000 stock, £7530.
15. 83-8967, 1.9387.
17. ·2036. 18. 240.
20. £1763. 1s.

10. a3 + b3 + c3 + 3 a2b + 3 ab2 a2c ac2 b2c - bc2

- 2 abc.

11. x2 + y2 + 24

4x3y + 4x3% 4 xy3 - 4 y3z + 4 xz3

- 12x2yz + 12 xy3z

= 12.

12. 0.

6.

{a

(bc)} - d.

(6 a7b)-(3c5d), 6a+ (76 - 3c + 5 d),

-{6a (76-3c)} + 5 d.

а

7. (4x3- 12 x'y)
- 4x3 (12x2y -
+
{4 203

8. (a3

(12 x2y

{a3 - (b3 + c3)} + 3abc.

(12 xy - xy3),

(a7bc) y − (b − c + d) z.

+ (x − y) ab + (y
y) ab + (y - 2) b2.

VI.-PAGE 161.

1. 12 a ab 662, 18 x

2. 23-2xy + 4 y3, xy2+

3. a1 + 2 a2b2 + ba,

9 xy - 35 y3.

5. a3 + b3 + c3 3 abc.

11. af

(ac + bƒ) x + (b + ƒ) cx2 + (c2 + dƒ) x + cdx.

12. 23 (pa) x2 + (q +

ap) x

aq.

13. x3 + (a + b + c) x2 + (ab + ac + bc) x + abc.

VII.-PAGE 165.

1. x2-2xy + y2, 9 a2 - 30 ab + 25 b2, 16 c + 8 c2ď2 + d3,

4. (a+c) (b + d)3, (a + b)2 - (c + d)2.

6. x+4x5, x2+7x+10, x2+ 2 x 15, x2- 25.

−

2. 2 a 5 a3b + 3o a2b2, 2x2 + 3 xy + 2y2.
3. axm
cm−n + bx¬"y" + cx−(m+n) yan,

8.x + x3y + x2y2 + xy3 + y2, x* - x3y + x2y2 - xy3 + y.

(a + b + c − d) (a + b − c + d) (a − b + c + d) (a−b - c - d):