The internal measures of a cuboidal room are 10 m X 5m X 4m. Find the cost of painting thefour walls of a room, if the cost of painting is Rs. 40 per m2. If the ceiling of the room is also to bepainted, what will be the total cost?

To solve this problem, we need to find the area of the walls and ceiling of the room and then multiply it by the cost of painting per square meter.

Step 1: Calculate the area of the four walls. The area of the four walls of a cuboidal room is given by the formula 2*(length + breadth)height. So, the area of the four walls = 2(10m + 5m)4m = 215m*4m = 120 square meters.

Step 2: Calculate the cost of painting the four walls. The cost of painting the four walls = area of the four walls * cost of painting per square meter. So, the cost of painting the four walls = 120 square meters * Rs. 40 per square meter = Rs. 4800.

Step 3: Calculate the area of the ceiling. The area of the ceiling of a cuboidal room is given by the formula lengthbreadth. So, the area of the ceiling = 10m5m = 50 square meters.

Step 4: Calculate the cost of painting the ceiling. The cost of painting the ceiling = area of the ceiling * cost of painting per square meter. So, the cost of painting the ceiling = 50 square meters * Rs. 40 per square meter = Rs. 2000.

Step 5: Calculate the total cost of painting. The total cost of painting = cost of painting the four walls + cost of painting the ceiling. So, the total cost of painting = Rs. 4800 + Rs. 2000 = Rs. 6800.

Therefore, the total cost of painting the four walls and the ceiling of the room is Rs. 6800.