# Average Tricks

If you want to do a government job, then rather than to prepare for a competition exam you have no other option to crack the exam. Whether it is SSC or banking or railway, you have to prepare well for it. If you are preparing for one of the examination, then you must be aware that the time for these exams is very short and the questions are very long. In such condition, you can ensure your selection by solving as many questions in a short time as possible with short cut tricks.

Through this page we are going to tell you about the Average Short Tricks. Average is a very easy topic in which you can easily get marks. In almost all competitive exams like SSC, Bank, Railway and other examination 2 to 3 questions are asked from the average topic. Here we are telling some Average Tricks with the help of which you can solve the average questions in a few seconds.

recruitmentresult.com

Average Formula: –

## Average Short Tricks (औसत शॉर्ट ट्रिक्स) In Hindi

 Trick 1

Tricks to solve problems based on calculating quantity in the group

In case of increase in average

Direct formula: Value of new quantity = New average + (No. of old quantities × increase in average)

Example: The average of 20 students is 12 years, if the teacher’s age is included, average increases by one. Find the age of the teacher.

Solution:

By using formula –

Age of the teacher = New average + (No. of old members × increase in average)

= 13 + (20 x 1) = 13 + 20 = 33 years

उदाहरण: एक क्लास में 30 स्टूडेंट की औसत आयु 14 वर्ष है, इसमें एक टीचर की आयु शामिल कर ली जाती है तो औसत क्लास की औसत आयु 15 वर्ष हो जाती है। ऐसे में टीचर की आयु ज्ञात किजिए।

समाधान:

इस तरह के प्रश्नों के लिए सूत्र

टीचर की आयु = नया औसत + (सदस्यों की पुरानी संख्या x औसत में वृद्धि)

= 15 + (30 x 1)

= 45 (टीचर की आयु 45 वर्ष है।)

In case of decrease in average

Direct formula: Value of removed quantity = New average + (No. of old quantities × decrease in average)

Example: The average age of 50 students and a teacher is 25 years. When the teacher’s age is excluded, the average age decreases by 1 year. What is the age of the teacher?

Solution:

By using formula –

Age of the teacher = New average + (No. of old quantities × decrease in average)

= 24 + (51 x 1) = 24 + 51 = 75 years

उदाहरण: 24 लड़कों और शिक्षक की औसत आयु 15 वर्ष है। जब शिक्षक की आयु को बाहर रखा जाता है, तो औसत 1 से घट जाता है। शिक्षक की आयु क्या है?

समाधान:

इस तरह के प्रश्नों के लिए सूत्र

टीचर की आयु = नया औसत + (सदस्यों की पुरानी संख्या x औसत में कमी)

= 14 + (25 x 1)

= 39 (टीचर की आयु 39 वर्ष है।)

Check Here – How to Prepare Maths for Competitive Exams

 Trick 2

The average of ‘n’ quantities is equal to ‘x’. If one or more of the given quantities whose value (p, q, r….) are replaced by a new quantities having value (p’, q’, r’…), the average becomes ‘y’

If the average age is increased, then

Direct formula: Total value of new quantities = Total value of removed quantities + (No. of persons × increase in average)

Example: The average weight of 20 students in a class is increased by 0.75 kg when one student of 35 kg replaced by a new student. Weight of the new student (in kg) is:

Solution:

By using formula –

Weight of the new student = Weight of separated student + (Increase in average × total number of students)

= 35 + (0.75 x 20) = 35 + 15 = 50 Kg

उदाहरण: चार व्यक्तियों का औसत वज़न 3 किलोग्राम बढ जाता है यदि 120 किलोग्राम वज़न वाले व्यक्ति के स्थान पर किसी और व्यक्ति को शामिल कर लिया जाता है। नए व्यक्ति का वजन ज्ञात करें।

समाधान:

इस तरह के प्रश्नों के लिए सूत्र

नए व्यक्ति का वजन = अलग हुए व्यक्ति का वजन + (औसत में वृद्धि x व्यक्तियों की संख्या)

= 120 + (3 x 4) = 120 + 12 = 132 किलोग्राम

If the average age is decreased, then

Direct formula: Total value of new quantities = Total value of removed quantities – (No. of persons × decrease in average)

Example: The average weight of 10 men is decreased by 3 kg when one of them whose weight is 80 kg is replaced by a new man. What is the weight of the new man?

Solution:

By using formula –

Weight of the new man = Weight of separated man – (No. of persons × decrease in average)

= 80 – (10 x 3) = 80 – 30 = 50 years

उदाहरण: 5 व्यक्तियों का औसत वजन 2 किलो कम हो जाता है जब कोई व्यक्ति 50 किलोग्राम वजन के स्थान पर आता है। नए व्यक्ति का वजन क्या है?

समाधान:

इस तरह के प्रश्नों के लिए सूत्र

नए व्यक्ति का वजन = अलग हुए व्यक्ति का वजन – (औसत में कमी  x व्यक्तियों की संख्या)

= 50 – (2 x 5) = 50 – 10 = 40 किलोग्राम

 Trick 3

The average of marks obtained by ‘n’ candidates in a certain examination is ‘T’. If the average marks of passed candidates is ‘P’ and that of the failed candidates is ‘F’. Then

Example: The average of marks obtained by 100 candidates in a certain examination is 30. If the average marks of passed candidates is 35 and that of failed candidates is 10, what is the number of candidates who passed the examination?

Solution:

By using formula –

उदाहरण: एक कक्षा में, 75 छात्र हैं और वार्षिक परीक्षा में उनके औसत अंक 35 हैं। यदि उत्तीर्ण छात्रों का औसत अंक 55 है और असफल छात्रों का औसत अंक 30 है, तो क्या आप उन छात्रों की संख्या का पता लगा सकते हैं जो असफल रहे?

समाधान:

इस तरह के प्रश्नों के लिए सूत्र

Also Check – Maths Formulas

 Trick 4

If the average age of ‘m’ boys is ‘x’ and the average age of ‘n’ boys out of in ‘m’ boys is ‘y’, then

Example: The average age of 30 students in a class is 12 years. The average of a group of the 5 students is 12 years. Find the average age of the remaining students.

Solution:

Here, m = 30, x = 12, n = 5 and y = 12

By using formula –

उदाहरण: 4 महिलाओं की औसत आयु 50 है। उनमें से तीन की औसत आयु 48 है। अन्य की उम्र क्या है?

समाधान:

यहाँ, m = 4, x = 50, n = 3 और y = 48

इस तरह के प्रश्नों के लिए सूत्र

 Trick 5

If the average of ‘m’ quantities is ‘x’ and the average age of ‘n’ quantities is ‘y’, then

Example: If the average age of 15 men is 40 years, and the average age of 10 women is 30, what is the average age of all 25 people?

Solution:

Here, m = 15, x = 40, n = 10 and y = 30

By using formula –

उदाहरण: एक वर्ग के दो सेक्शन A और B हैं, जिनमें क्रमशः 36 और 44 छात्र हैं। यदि सेक्शन A का औसत वजन 40 kg है और सेक्शन B का औसत वजन 35 kg है, तो पूरी कक्षा का औसत भार ज्ञात करें।

समाधान:

यहाँ, m = 36, x = 40, n = 44 और y = 35

इस तरह के प्रश्नों के लिए सूत्र