Find the smallest number which leaves remainder 8 and 12 when divided by 28 and 32 respectively.

Asked by Last Modified  

3 Answers

Learn Mathematics +1

Follow 3
Answer

Please enter your answer

Science Tutor

Here is a general way to solve. It is equivalent to solving the system: {x≡8x≡12mod28,mod32.{x≡8mod28,x≡12mod32. There is a formula when the moduli are coprime. We'll reduce the problem to this case. Any solution has to be divisible by 44, so we'll set x=4yx=4y. The congruences can be written as {4y≡8mod284y≡12mod32⟺{y≡2mod7y≡3mod8 {4y≡8mod284y≡12mod32⟺{y≡2mod7y≡3mod8 Now...
read more
Here is a general way to solve. It is equivalent to solving the system: {x≡8x≡12mod28,mod32.{x≡8mod28,x≡12mod32. There is a formula when the moduli are coprime. We'll reduce the problem to this case. Any solution has to be divisible by 44, so we'll set x=4yx=4y. The congruences can be written as {4y≡8mod284y≡12mod32⟺{y≡2mod7y≡3mod8 {4y≡8mod284y≡12mod32⟺{y≡2mod7y≡3mod8 Now a Bézout's relation between 77 and 88 is 8−7=18−7=1, hence the solutions for yy are y≡2⋅8−3⋅7=−5mod56, y≡2⋅8−3⋅7=−5mod56, whence x=4y≡−20mod224x=4y≡−20mod224. So the smallest positive value is x=204x=204. Added: More generally, one shows a system of linear congruences x≡aimodmi(i=1,…,r) x≡aimodmi(i=1,…,r) where the mimi are not necessarily mutually coprime, has a solution if and only if ∀i∀j,ai≡ajmodgcd(mi,mj) ∀i∀j,ai≡ajmodgcd(mi,mj) and in this case, the solution is unique modulo lcm(m1,…,mr)lcm⁡(m1,…,mr). read less
Comments

Tutor

By remainder theorem n=(p×q)+r, where n=number, p=divisor, q=quotient, r=remainder From given data x=28y+8, x=32y+12 y=(x-8)/28, y=(x-12)/32 (x-8)/28=(x-12)/32 8(x-8)=7(x-12) 8x-64=7x-84 x=-84+64 x=-20 The smallest number is -20
Comments

Math magician

the smallest number that will be devided by 28 and 32 is ,their LCM = 224 , but there remainder 8 when devide by 28 , so 28 - 8 = 20. remainder 12 when devide by 32 . so 32 - 12 = 20 . Now 224 - 20 = 204 answer.
Comments

View 1 more Answers

Related Questions

How was algebra discovered?
The development of algebra was a gradual process that took place over many centuries and involved contributions from various civilizations. 1)Ancient Babylonians (2000-1600 BCE) 2)Ancient Egyptians...
Naveen
0 0
7
Is it possible to construct a triangle by taking two of its angle: 70, 115?
NOSum of all the angles of a triangle is 180.As 70+115 is exceeding 180 degrees, it is not possible to construct a triangle.
Prasenjit
What is an algebra?
Combination of literals and constant with Arithmetical operations.
Mang
0 0
7

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons



Class X Trignometry
Class X - Trignometry. In a Right angle triangle, Sineθ = opposite/hypotenues Cosθ = adjacent/hypotenues Tanθ = opp/ajd secθ = hyp/adj cosesθ = hyp/opp cotθ =...


PYQ MATHS GRADE 10 Ways to Extract questions
How to Find Important Questions for CBSE Exams: 1. Go to Google and type “PYQ Important Questions Learn CBSE”. 2. To get topic-specific questions, type “PYQ Grade 10 Mathematics ”. 3....

Recommended Articles

Sandhya is a proactive educationalist. She conducts classes for CBSE, PUC, ICSE, I.B. and IGCSE. Having a 6-year experience in teaching, she connects with her students and provides tutoring as per their understanding. She mentors her students personally and strives them to achieve their goals with ease. Being an enthusiastic...

Read full article >

Mohammad Wazid is a certified professional tutor for class 11 students. He has 6 years of teaching experience which he couples with an energetic attitude and a vision of making any subject easy for the students. Over the years he has developed skills with a capability of understanding the requirements of the students. This...

Read full article >

Quest Academy is a professional Bangalore based NEET and JEE (Main + Advanced) training institute. The academy was incorporated in 2015 to cater to the needs of students, who aim to crack competitive exams by connecting with the best brains around. The institute helps students enhance their skills and capabilities through...

Read full article >

Raghunandan is a passionate teacher with a decade of teaching experience. Being a skilled trainer with extensive knowledge, he provides high-quality BTech, Class 10 and Class 12 tuition classes. His methods of teaching with real-time examples makes difficult topics simple to understand. He explains every concept in-detail...

Read full article >

Looking for Class 10 Tuition ?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you