Quantitative Aptitude in easy way

HCF means Highest Common Factor: HCF of two or more numbers is the greatest number that divides each of them exactly. We are going to practice question like first simple, little bit tuff and more tuff. Tuff means the question takes more time for calculation that’s it ok. I will give some tips for quicker calculation methods also. Ex. 1 Find the HCF of 42 and 70             42 = 2x3x7             70 = 2x5x7  HCF = 2x7=14                         Quicker method             70 - 42 =28             42 -28=14             28-14=14             14-14=0           HCF =14 Ex. 2 Find the HCF of 1365,1560 and 1755             1365=3x5x7x13             1560=2x2x2x3x5x13             1755=3x3x3x5x13      HCF=3x5x13=195 in this method we have to spend little bit more time  Quicker method          1560-1365=195             1755-1560=195           HCF = 195 HCF of decimals Rule first make (if necessary) the same number of decimal places in all g

Cubes of large numbers are rarely used. Here we are going to practice two-digit number.. First we have remember the cubes up to 10 1 3   = 1               2 3 = 8                3 3 = 27              4 3 = 64              5 3 = 125                                    6 3 = 216            7 3 = 343            8 3 = 512            9 3 = 729            10 3 = 1000 If two digit number starts with 1 like 11 12 13 14 15 16 17 18 19 to calculate the cubes of these Ex 1.      1 2 3   = Step I:              1   2   4 8 (double the previous ones)               ( 2x2=4 and 4x2=8) Step II:              4 8           (Step I middle numbers multiply with 2)                         (2x2=4 and 4x2=8) ADD Step I   and   Step II                         1 2 4 8                              4 8                            __________                           1 7 2 8   answer Ex 2.      1 6 3   = Step I:               1      6     36   216 (double the prev

Squaring is intimately connected with a procedure known as the Duplex Combination process. Example: Duplex of 2 is 2 2 =4 If you want to know Ex: 3 4 2 Step I          : 3 2 / 2( 3 x 4 ) / 4 2 Step II         :9 / 24 / 16  Answer       :11/ 2 5/ 1 6 =>1156 Ex: 3 4 6 Step I          : 3 2 / 2( 3 X 4 ) / 2( 3 X 6 ) + 4 2 / 2( 4 X 6 ) / 6 2 Step II         :  9 / 24             /          52      /48     /36 Answer       : 11 / 2 9 /                     5 7        / 5 1      / 3 6   =>119716 Ex: 8 4 3 2 Step I          : 8 2 / 2( 8 X 4 ) / 2( 3 X 8 )+ 4 2 / 2( 8 X 2 ) + 2( 3 X 4 ) / 2( 4 X 2 ) + 3 2 / 2( 3 X 2 ) / 2 2 Step II         :  64 / 64          / 64    /          56       /25     /12     /4                      Answer       :71 / 7 0  / 6 9      / 5 8      / 2 6      / 1 2      /          4 => 71098624 Ex : 73214 2 =53 4 6 4 0 3 2 6 8 2 9 1 79 1 6=>5360289796 Special cases like numbers end’s with 5

I suggest you to remember the tables up to 9 because it saves some valuable time during calculation. Let us look at the case of multiplication by a number more than 10 5892 X 11 05892 X 11 STEP I    :(2 X 1)                  = 2 STEP II   :(9 X 1)+2             = 1 12 STEP III :(8 X 1)+9+1        = 1 812    STEP IV :(5 X 1)+8+1        = 1 4812 STEP V  :(0 X 1)+5+1        =64812 5324 X  12 05324 X 12 STEP I    :(4X 2)                   =8 STEP II   :(2 X 2)+4             =88 STEP III :(3 X 2)+2             =888   STEP IV :(5 X 2)+3             = 1 3888 STEP V   :(0 X 2)+5+1       =63888 If you go through it yourself you will find that calculation goes very fast and easy… 17 x 18                             STEP I        : (7 X 8) = 5 6                             STEP II       : (1 X 8)+ (7 X 1) = 2 06                             STEP III     : (1 X 1)+2=306                             AN OTHER METHOD 18 ROUND FIGURE IS 20