Total number of plants planted by all of them = 48 + 31 + 29 + 28 = 136 136 is sum of first 16 natural numbers, i.e. 1 + 2 + 3 + .............+ 15 + 16 = 136 The minimum number of plants planted for a variety is 1, and the maximum is 16. Therefore, the total number of varieties of plants cannot exceed 16, but if it is less than 16, i.e. if it is 15 or 14, it doesn’t satisfy the sum value of 136, or the maximum number of plants planted for a variety is 16. This implies that all of them have planted 16 varieties of plants. It is mentioned that each one has planted a minimum of two varieties of plants and a maximum of six varieties. Sum = 2 + 3 + 4 + 5 + 6 = 20 Removing 4, we will get 16 total varieties for four members. Therefore, four of them planted 2, 3, 5, and 6 varieties of plants in any order. It is given that, The number of plants planted by a person for each variety is in A.P. The number of plants planted by another person for each variety is in G.P. They have planted more than three varieties of plants. This means that they have planted 5 and 6 varieties in any order.
Sum of A.P series = $$\frac{n}{2}\left(2a+\left(n-1\right)d\right)$$ The Sum of an A.P series is always divisible by $$\frac{n}{2}$$ (n - number of terms) Out of the given values, the only possible value is 48, which is divisible by 3 (6/2) Therefore, a person has planted 48 plants of 6 varieties. A person has planted 48 plants of 6 varieties in A.P Let us assume she has planted a-5d, a-3d, a-d, a+d, a+3d, and a+5d plants of each variety. Sum = 48 6a = 48 a = 8 Number of plants planted are 8-5d, 8-3d, 8-d, 8+d, 8+3d, 8+5d The only possible value for d is 1 Therefore, the only possibility is that she has planted 3, 5, 7, 9, 11, and 13 (6) plants of each variety.
The person who planted the plants of different varieties in G.P has planted five varieties. Sum of G.P series = $$\ \frac{\ a\left(r^n-1\right)}{r-1}=\ \frac{\ a\left(r^5-1\right)}{r\ -1}=a\left(r^4+r^3+r^2+r+1\right)$$ Out of the given values, only possible value is 31 i.e. a = 1 and r = 2. The number of plants planted in each variety is 1, 2, 4, 8, 16 (5) in any order. In the table, it is given that Aashi has planted two rose plants. This implies that she has planted the plants in G.P.
Remaining numbers: 6, 10, 12, 14, 15 A person has planted two varieties of plants, and the number of plants planted is either 28 or 29. The only possibility is she has planted 14, 15 plants of each variety in any order. It is mentioned that Nitya has planted 6 Banyan trees. This implies that Nitya has planted 6, 10, and 12 plants of each variety in any order.
It is mentioned that the maximum difference between the total number of plants of any two varieties is one. Therefore, let us assume there are x varieties with y plants and (6-x) with y-1 plants, i.e. xy + (6-x)(y-1) = 136 xy + 6y - 6 - xy + x = 136 x + 6y = 142 (x<6) The only possibility is x = 4, y = 23 Therefore, there are 23, 23, 23, 23, 22 and 22 plants of each variety in any order. The only possibility for the number of neem plants is 23 (9+0+14+0) The number of coconut plants can be 22 or 23. Therefore, the remaining sum should be 11 or 12 For 11: (1, 0, 10) For 12: (2, 0, 10) we cannot consider 12, as Aashi has planted two mango plants. Therefore, it should be 11 (1, 0, 10).
The number of rose plants planted by Nitya cannot be 12. If it is 12, the remaining sum should be either 8 or 9, which is impossible. Therefore, the number of rose plants planted by Nitya will be 0. If it is 0, the remaining sum should be 20 or 21. For 21: 7, 14, 0 For 20: 5, 15, 0 It cannot be 21 as 14 neem plants are planted; therefore, the remaining sum will be 20(5,15,0)
The remaining sum for the number of Banyan trees should be 17. The only possibility is (13,4)Final arrangements:
It is mentioned that Puja has planted 7 teak plants, this refers to case 2b, i.e.
A) Total number of mango plants = 23 B) Teak plants planted by Puja + Neem plants planted by Manu = 7 + 14 = 21 C) Banyan plants planted by Puja + Mango plants planted by Nitya = 13 + 12 = 25 D) Mango plants planted by Aashi + Rose plants planted by Manu = 8 + 15 = 23 Option C has maximum value.
Therefore, answer is option C.