**The sum of the dimensions of a room (i.e. length, breadth and height) is 18 metres and its length, breadth and height are in the ratio of 3 : 2 : 1 respectively. If the room is to be painted at the rate of Rs. 15 per m**^{2}, what would be the total cost incurred on painting only the four walls of the room (in Rs.)?- 3250
- 2445
- 1350
- 2210
- 2940

Answer : Option C.

Ratio of length : breadth : height = 3 : 2 : 1

Breath = 2/6×18 = 6

Height = 1/6×18 = 3

Area of four walls = 2h×(l+b) = 2×3(9+6) = 90

Total cost of painting four walls = 90×15 = 1350**B is 4/3 times as efficient as A. If A can complete 5/8th of a given task in 15 days, what fraction of the same task would remain incomplete if B works on it independently for 10 days only?**- 3/4
- 2/3
- 5/8
- 4/9
- 2/3

Answer : Option D.

B is 4/3 times as efficient of A.

Ratio of time taken by A and B, A: B is 4:3.

A can complete 5/8th of a given task in 15 days

A can do alone his work in = 8/5× 15= 24 days

Therefore, B can do this work= 18

B works independently for 10 days only, thus work done = 10/18 = 5/9

Remaining work (incomplete) = 1-5/9 = 4/9

**In a class, the average weight of boys is 64 kg and that of 75 girls is 70 kg. After a few days, 60% of the girls and 30% of the boys leave. What would be the new average weight of the class (in kg)? Assume that the average weight of the boys and the girls remain constant throughout.**- 63
- 66.5
- 68.5
- 65.5
- Can't be determined

Answer : Option E.

In this question, number of boys is not mentioned .So, we can’t find new average.**382 380 374 356 302 ?**- 212
- 240
- 140
- 201
- 158

Answer : Option C.

The pattern is as follows:

382 – 2 = 380

380 – 6 = 374

374 – 18 = 356

356 – 54 = 302

302 – 162 = 140**3 9 45 315 ? 31185**- 2465
- 2685
- 2955
- 2835
- 2785

Answer : Option D.

The pattern is as follows:

3 * 3 = 9

9 * 5 = 45

45 * 7 = 315

315 * 9 = 2835Saint-Gobain Preparation Links- Sample Aptitude Questions of Saint-Gobain
- All About Saint-Gobain
- Free Mock Saint-Gobain Placement Paper
- Join free prep course for Saint-Gobain
- Test Pattern & Selection Procedure of Saint-Gobain

**12 14 18 26 42 ?**- 106
- 74
- 92
- 68
- 84

Answer : Option B.

The pattern is as follows:

12 + 2 = 14

14 + 4 = 18

18 + 8 = 26

26 + 16 = 42

42 + 32 = 74**In how many ways can 3 integers be selected from the set {1, 2, 3, …….., 37} such that sum of the three integers is an odd number?**- 3876
- 7638
- 6378
- 1938
- 969

Answer : Option A.

There are 18 even and 19 odd numbers in the given set. For sum to be odd either all 3 numbers should be odd or 2 of them even and one odd. This is possible in^{19}C_{3}+ (^{18}C_{2}×^{19}C_{1}) = 3876 ways**There are 13 married couples, 5 single men and 7 single women in a party. Every man shakes hand with every woman once, but no one shakes hand with his wife. How many handshakes took place in the party?**- 247
- 347
- 360
- 191
- 100

Answer : Option B.

Any single man will have = 13 + 7 = 20 options.

Total number of handshakes by single men = 20 × 5= 100. Any married man will have 12 + 7 = 19 options.

Total number of handshakes by married men = 19 × 13 = 247. Total number = 247 + 100 = 347.**A and B are two towns. A car goes from A to B at a speed of 64 km/hr and return to A at a slower speed. If its average speed for the whole journey is 56 km/hr, it returned with speed**- 152.54 km/hr
- 47.52 km/hr
- 49.78 km/hr
- 53 km/hr
- 57 km/hr

Answer : Option A.

Let the speed on the return journey be x km/hr. Then, 56 = = 7(64 + x) = 16x or 9x = 448 ∴ x = 448/9 = 49.78 km/hr.**A train travels 225 km in 3.5 hours and 370 km in 5 hours. Find the average speed of train.**- 80 km/hr
- 60 km/hr
- 70 km/hr
- 63 km/hr
- 50 km/hr

Answer : Option C.

Here, x_{1}= 225, x_{2}= 370, T_{1}= 3.5 and T_{2}= 5.

∴ Average speed of train = (X_{1}+ X_{2})/(T_{1}+ T_{2}) = (225+370)/(3.5+5) = 70 km/hr.