Answer: After 12 days, they receive both again.
Step-by-step explanation:
Since we have given that
Every 4 th day grocery store gets a shipment of pineapples.
Every 6 th day grocery store gets a shipment of bananas.
We need to find the number of days that they will receive both again.
We will do "LCM" of 4 and 6.
L.C.M. of 4 and 6 = 12
So, after 12 days, they receive both again.