00:01
Hi, in this question given that a is directly proportional to mn2 and inversely proportional to y3.
00:13
So, we can form this.
00:15
So, here we have to remove directly proportional to equal.
00:20
So, we have to add the constant.
00:22
So, a equals k mn2 divided by y3 which is the required equation and here we need to find the value of k when a equals 9 and here m equals 16, n equals 9 and y equals 3.
00:41
On substituting all the known values in this, then we get 9 equals k into 16 into 9 the whole square divided by 3 cube which is equal to 9 equals k into 16 into 9 square is 81 divided by 3 cube is 27.
01:02
So, we can write it as k equals 9 into 27 divided by 16 into 81.
01:17
So, here 1 9th are 9 and here 9 9th are 81 and here 3 9th are 27, 1 9th are 9...