What is the least number which when divider by 12,18 and 21 leaves a remainder of 3​

12=2^2×3

18=2×3^2

21=3×7

hence

lcm(12,18,21)=2^2×3^2×7=252

now it leaves remainder 3

hence

the number is 252+3= 255

Step-by-step explanation:

option 1 is correct.

step-by-step explanation:

y varies inversely with x and constant of variation is 4

the equation will be:

y = k/x

where k =4 so,

y = 4/x

if we put values of x of option 1 in the above equation and find values of y

y = 4/-2 => y =-2

y = 4/-1 => y = -4

y = 4/1 => y = 4

y = 4/2 => y =2

so, all the values of x and y are correct.

if we put values of x given in other options and find value of y we cannot find whole table satisfying the equation.

hence option 1 is correct.