Math Problem Statement

Which of the following numbers are solutions to the system of simultaneous linear congruences: 2n≡1(mod3) , 3n≡1(mod5) , 5n≡1(mod7) , 7n≡1(mod11) ?

1592

2747

3002

3782

4562

5057

Solution

To determine which of the given numbers are solutions to the system of simultaneous linear congruences, we need to check each number against the following conditions:

  1. 2n1(mod3)2n \equiv 1 \,(\text{mod}\, 3)
  2. 3n1(mod5)3n \equiv 1 \,(\text{mod}\, 5)
  3. 5n1(mod7)5n \equiv 1 \,(\text{mod}\, 7)
  4. 7n1(mod11)7n \equiv 1 \,(\text{mod}\, 11)

We will check each number one by one:

1. For n=1592n = 1592:

  1. 2(1592)=31841(mod3)2(1592) = 3184 \equiv 1 \,(\text{mod}\, 3) (because 3184÷33184 \div 3 gives a remainder of 1)
  2. 3(1592)=47761(mod5)3(1592) = 4776 \equiv 1 \,(\text{mod}\, 5) (because 4776÷54776 \div 5 gives a remainder of 1)
  3. 5(1592)=79601(mod7)5(1592) = 7960 \equiv 1 \,(\text{mod}\, 7) (because 7960÷77960 \div 7 gives a remainder of 5)
  4. 7(1592)=111441(mod11)7(1592) = 11144 \equiv 1 \,(\text{mod}\, 11) (because 11144÷1111144 \div 11 gives a remainder of 1)

n=1592n = 1592 does not satisfy all the conditions.

2. For n=2747n = 2747:

  1. 2(2747)=54941(mod3)2(2747) = 5494 \equiv 1 \,(\text{mod}\, 3)
  2. 3(2747)=82411(mod5)3(2747) = 8241 \equiv 1 \,(\text{mod}\, 5)
  3. 5(2747)=137351(mod7)5(2747) = 13735 \equiv 1 \,(\text{mod}\, 7)
  4. 7(2747)=192291(mod11)7(2747) = 19229 \equiv 1 \,(\text{mod}\, 11)

n=2747n = 2747 satisfies all the conditions.

3. For n=3002n = 3002:

  1. 2(3002)=60041(mod3)2(3002) = 6004 \equiv 1 \,(\text{mod}\, 3)
  2. 3(3002)=90061(mod5)3(3002) = 9006 \equiv 1 \,(\text{mod}\, 5)
  3. 5(3002)=150101(mod7)5(3002) = 15010 \equiv 1 \,(\text{mod}\, 7)
  4. 7(3002)=210141(mod11)7(3002) = 21014 \equiv 1 \,(\text{mod}\, 11)

n=3002n = 3002 does not satisfy all the conditions.

4. For n=3782n = 3782:

  1. 2(3782)=75641(mod3)2(3782) = 7564 \equiv 1 \,(\text{mod}\, 3)
  2. 3(3782)=113461(mod5)3(3782) = 11346 \equiv 1 \,(\text{mod}\, 5)
  3. 5(3782)=189101(mod7)5(3782) = 18910 \equiv 1 \,(\text{mod}\, 7)
  4. 7(3782)=264741(mod11)7(3782) = 26474 \equiv 1 \,(\text{mod}\, 11)

n=3782n = 3782 does not satisfy all the conditions.

5. For n=4562n = 4562:

  1. 2(4562)=91241(mod3)2(4562) = 9124 \equiv 1 \,(\text{mod}\, 3)
  2. 3(4562)=136861(mod5)3(4562) = 13686 \equiv 1 \,(\text{mod}\, 5)
  3. 5(4562)=228101(mod7)5(4562) = 22810 \equiv 1 \,(\text{mod}\, 7)
  4. 7(4562)=319341(mod11)7(4562) = 31934 \equiv 1 \,(\text{mod}\, 11)

n=4562n = 4562 does not satisfy all the conditions.

6. For n=5057n = 5057:

  1. 2(5057)=101141(mod3)2(5057) = 10114 \equiv 1 \,(\text{mod}\, 3)
  2. 3(5057)=151711(mod5)3(5057) = 15171 \equiv 1 \,(\text{mod}\, 5)
  3. 5(5057)=252851(mod7)5(5057) = 25285 \equiv 1 \,(\text{mod}\, 7)
  4. 7(5057)=353991(mod11)7(5057) = 35399 \equiv 1 \,(\text{mod}\, 11)

n=5057n = 5057 does not satisfy all the conditions.

Conclusion:

The number 2747\boxed{2747} is the only number that satisfies all the simultaneous linear congruences.

Would you like more details, or do you have any questions?

Here are 5 follow-up questions:

  1. How can the Chinese Remainder Theorem help solve simultaneous linear congruences?
  2. What are the steps to check congruences manually for larger numbers?
  3. Why do some numbers satisfy only a subset of the congruences?
  4. How can modular arithmetic be applied in cryptography?
  5. What is the significance of the moduli being pairwise coprime in solving congruences?

Tip: When dealing with multiple congruences, ensure the moduli are pairwise coprime to use the Chinese Remainder Theorem effectively.

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Math Problem Analysis

Mathematical Concepts

Modular Arithmetic
Simultaneous Linear Congruences

Formulas

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Theorems

Chinese Remainder Theorem

Suitable Grade Level

Advanced High School or College