Correct Answer:
Option B - Minimum number of plants of each type planted by the farmer = LCM of 70, 28, and 42
70 = 2 × 5 × 7
28 = 2 × 2 × 7
42 = 2 × 3 × 7
LCM • 2 × 2 × 3 × 5 × 7
= 420
Hence the Minimum number of plants = 420
B. Minimum number of plants of each type planted by the farmer = LCM of 70, 28, and 42
70 = 2 × 5 × 7
28 = 2 × 2 × 7
42 = 2 × 3 × 7
LCM • 2 × 2 × 3 × 5 × 7
= 420
Hence the Minimum number of plants = 420