Question
A cube of side length 5 cm is painted on all its faces
and then cut into smaller cubes of side length 1 cm. How many smaller cubes have no paint on them?Solution
The large cube has a side length of 5 cm, and it is cut into smaller cubes with side length 1 cm. The number of smaller cubes created is (5/1) Γ(5/1) Γ(5/1) =125smaller cubes in total. The smaller cubes that have no paint on them are those in the center of the large cube. These cubes are completely surrounded by other cubes and are not exposed to any painted faces. To find the number of cubes with no paint, we consider the smaller cube formed in the center, which has side length 3 cm (since the cubes on the outer layer have paint). Thus, the number of smaller cubes with no paint on them is 3Γ3Γ3=27. Therefore, the correct answer is (b), 27.
P, Q started a business along with R. The initial investment of P is 20% less than the initial investment of Q. The ratio between the initial investment...
'A', 'B' and 'C' started a partnership business with capital of Rs. 5000, Rs. 7000 and Rs. 9000 where all three invested for equal time. If the profit ...
Deepak, Mohit, and Sneha started a business with initial investments in the ratio 3:4:6 respectively. After one year, Sneha, Deepak, and Mohit made addi...
A and B entered into a business investing Rs. (x + 77) and Rs. (x β 55) respectively. After one year they invested Rs. 40 more and Rs. 159 more respec...
- Arjun and Karan became partners in a startup. Arjun invested Rs. 7,200. Karan exited the business after 10 months. Their profit shares were in the ratio of...
A and B invested Rs. 3600 and Rs. 4800 in a business. After 2 months, C joined with Rs. βxβ. If Aβs profit share in the total annual profit of Rs....
B invests double the money invested by A and triple the money invested by C. The ratio of period of investment between A, B and C is 1:2:3. Difference b...
A and B launched a business with initial investments of Rs. 2000 and Rs. 3600, respectively. Three months into the venture, C came on board with an inve...
In a business there are two partners βPβ and βQβ. βPβ started the business with the capital of Rs. 25000 and after 3 months βQβ joined h...
Three friends A, B and C entered into partnership by investing Rs. 40X, Rs. (5X + 1500) and Rs. (5000 β 10X) respectively. The ratio of the time peri...