If both sides of inequality is multiplied by negative quantity, then sign of inequality changes. Let -x< 5, then both sides is multiplied by -1 , (-1)(-x)>(-1)5.So x>-5. In this way,we can eliminate negative sign of variable.

2×3=6, 6x3=18 , 18×3= 54, 54×3 = 162

So here next no. is obtained by multiplying previous no by 3

So sequence will b

2,6,18,54,162 ......

2^(m-3)=1 or,2^(m-3)=2^(0).so (m-3)=0. Now,m=3.

3px-py+3qx-qy =p(3x-y)+q(3x-y)=(3x-y)(p+q)

Average income= Sum of incomes/total no. of incomes={4500+3550+4260+4880}/4=17190/4= 4297.50

If a+(-a)=0 then -a is additive inverse of a &a is additive inverse of (-a). So additive inverse of -8 is 8 because sum of these two quantities is zero.

Let no of notes of denomination of rs 10 = x,. & no of notes of denomination of rs 50=y. ATQ, 10x+50y=250. & x=y+1. From both equation,we get, 10(y+1) +50y=250, 10y+10+50y=250, 60y=240.so y=4 & x=y+1=5

In 52 minutes,car travelled 64kms, then in 1minute it can travel (64/52)km, so in 60 minutes,it can travel (64*60)/52 kms=73.85 . So speed of car is 73.85 km/hr

The average speed in km per hour is shown by:

Average speed = Total distance travelled / Time taken in hours

Hence the time given is minutes, we need to first 

52 minutes = 52 / 60 hours = 0.87 hours

Therefore, Average speed is

Average speed = 64 km / 0.87 hours = 73.56 km/hr

that is, the average speed of the car was 73.56 km/hr.

60% of 2nd Number = 25% of 1st Number

Let 2nd number be y and 1st number be x

60y/100 = 25x/100

Therefore, y = 5x/12

Hence, 80% of y = 80y/100 = (80×5x)/(100×12) = x/3 or 33.33% of x