भू-चुंबकत्व या पार्थिव चुंबकत्व | चुंबकत्व और द्रव्य Ch 5 Lec 3 | 12th/JEE/NEET Physics By Gopal Sir

The average of twelve numbers is 55.5. The average of the first four numbers is 53.4 and that of the next four numbers is 54.6. The 10th number is greater than the 9th number by 3 but lesser than the 11th and 12th numbers by 2 and 3, respectively. What is the average of the 10th and the 12th numbers? बारह संख्याओं का औसत 55.5 है | पहली चार संख्याओं का औसत 53.4 है तथा अगली चार संख्याओं का औसत 54.6 है | 10वीं संख्या 9वीं संख्या से 3 अधिक है लेकिन 11वीं और 12वीं संख्याओं से क्रमशः 2 और 3 कम है | 10वीं और 12वीं संख्याओं का औसत ज्ञात करें |

In a school 4/9 of the number of students are girls and the rest are boys 3/5 of the number of boys are below 12 years of age and 5/12 of the number of girls are 12 years or above 12 years of age. If the number of students below 12 years of age is 480, then 5/18 of the total number of students in the school will be equal to: एक विद्यालय में, छात्रो कौ कुल संख्या का 4/9 लडकियाँ और बाकी लडके है। लडको की कुल संख्या का 3/5 , 12 साल से कम है, और लडकियो की संख्या का 5/12 ,12 साल या उससे अधिक है। यदि 12 साल, से कम आयु के छात्रो की संख्या 480 है, तो स्कूल में छात्रो की कुल संख्या का 5/18 निम्न में से किसके बराबर है?

If 8 men or 12 boys can do a piece of work in 16 days, the number of days required to complete the work by 20 men and 6 boys is यदि 8 आदमी या 12 बालक एक काम को 16 दिन में कर सकते हैं, तो 20 आदमियों और 6 बालकों को वह काम पूरा करने में कितने दिन 7 लगेंगे? Options are (a) 5(1)/(3) (b) 6(1)/(3) (c) 8(1)/(3) (d) 7(1)/(7)

An examination was held during the 2 weeks of April 3rd-Sunday to 16th Saturday. There was 1 paper for the six subjects - Physics, Chemistry, Biology, Maths, English and Hindi. Only 1 paper per day No exam on Saturdays and Sundays and Holiday on April 5th. Only 3 exams were there in a week. Chemistry was before Biology and Maths was on the next day of Hindi. The day on which the paper of biology and maths were held was the same, while that for chemistry and physics was also the same. There was no exam for 3 days between Physics and the exam prior to it. Hindi exam on Tuesday and one exam between Hindi and English exam. There was at least a gap of one day between any 2 science paper. Which of the following exam was held on April 12th ?