Answer: D) 5 minutes Explanation: Let the total capacity of tank be 90 liters.Capacity of tank filled in 1 minute by K = 3 liters.Capacity of tank filled in 1 minute by L = 15 liters.Therefore, capacity of the tank filled by both K and L in 1 minute = 18 liters.Hence, time taken by both the pipes to overflow the tank = 90/18 = 5 minutes.

Answer: A) 0.5 Explanation: 80x900/100 + 256 x 4 x ? = 1331 - 99 720 + 1024 x ? = 1232 ? = 1232 - 720/1024 ? = 512/1024 = 0.5 ? = 0.5

Answer: A) 20% स्पष्टीकरण: अंग्रेजी में उत्तीर्ण छात्रों का प्रतिशत = 60% हिंदी में उत्तीर्ण छात्रों का प्रतिशत = 45% दोनों विषयों में उत्तीर्ण छात्रों का प्रतिशत = 25% एटीक्यू, केवल अंग्रेजी में उत्तीर्ण छात्रों का प्रतिशत = 60 - 25 = 35% का प्रतिशत विद्यार्थी केवल हिंदी में उत्तीर्ण हुए = 45 - 25 = 20% इसलिए, अनुत्तीर्ण छात्रों का प्रतिशत = 100 - (35 + 25 + 20) = 100 - 80 = 20%।

Answer: B) 7 hrs Explanation: Given, P can fill in 12 hrs Q can fill in 15 hrs R can fill in 20 hrs => Volume of tank = LCM of 12, 15, 20 = 60 lit => P alone can fill the tank in 60/12 = 5 hrs => Q alone can fill the tank in 60/15 = 4 hrs => R alone can fill the tank in 60/20 = 3 hrs Tank can be filled in the way that (P+Q) + (P+R) + (P+Q) + (P+R) + .... => Tank filled in 2 hrs = (5+4) + (5+3) = 9 + 8 = 17 lit => In 6 hrs = 17 x 6/2 = 51 lit => In 7th hr = 51 + (5+4) = 51 + 9 = 60 lit => So, total tank will be filled in 7 hrs.

Answer: C) Rs. 2160 Explanation: => 60x5 : 36x6 : 75x3 => 100 : 72 : 75 => 72/247 x 7410 = Rs. 2160

Answer: A) 63 and 49 Explanation: Since their HCFs are 7, numbers are divisible by 7 and are of the form 7x and 7y Difference = 14 => 7x - 7y = 14=> x - y = 2 product of numbers = product of their hcf and lcm=> 7x * 7y = 441 * 7=> x * y = 63 Now, we havex * y = 63 , x - y = 2=> x = 9 , y = 7 The numbers are 7x and 7y=> 63 and 49