SOLUTION IN 21 TO 30

21.       4500 x X= 3375  X = 3375      =3

                                    4500         4   

                       45) 3375  (75

                           315  

                            225

                              225

                                  x

22.       1400 x X =     1050 X = 1050      =   3

                                                1400           4

   

23.       Given exp. (1000)⁹ = (10³)⁹  =   10²⁷  = 10³ = 1000.

                         10²⁴     10²⁴          10²⁴       

        

24.       Given exp. 8988 x 1/8 x 1/4 = 2247/8    = 280.875

25.       Given exp. = 666 x 1/6 x 1/3 = 37.

                                 ²¹⁶   ³⁶ ⁹

26.       Given  300  x  1296        = 450

                                     64 ₄         8 ₆ ₄  

27.       Given exp. = (12³) x 6⁴ = (12)² x 6⁴   = (12)² x 6² = (72)² = 70.          

                          432               12 x 6²

28.       Given exp. = 35 + 15 x 3/2 = 35 + 45/2 = 35 + 22.5 = 57.5.

29.       5358 x 51 = 5358 x (50 + 1)      267900    

                       = 5358 x 50 + 5358 x 1                     + 5358           

                      =2679900 + 5358 = 27358.             273258

30.    587 x 999 = 587 x (1000 – 1)

                   =587 x 1000 – 587 – 1 = 587000 – 587 = 586413