4×25+ 16×25 4×25× 16×25 36×99

(25+ 15) ×4 (25× 15)×4 49×49+49×5 1

49×99+49 (68+32)×5 5×289×2

68+32×5 ( 125×25)×4 ( 125 + 17)×8

25×64× 125 85×82 + 82× 15 25×97 + 25×3

64× 15- 14× 15 125×88 88× 102

87×99 + 87 79×25 + 25 76× 10 1-76