Answer:
The correct answer is 218 math textbooks and 259 sociology textbooks.
Step-by-step explanation:
To solve this problem, we can make a system of equations. Let the number of sociology textbooks sold be represented by the variable "s" and the number of math textbooks sold be represented by the variable "m". Using these variables, we can make two equations:
s + m = 477
m + 41 = s
There are many ways to solve this system of equations. One approach we can take is substituting the value for s given by the second equation into the first equation. This is modeled below.
s + m = 477
(m + 41) + m = 477
Combining like terms on the left side of the equation yields:
2m + 41 = 477
Subtracting 41 from both sides of the equation gives us:
2m = 436
Finally, dividing both sides of the equation by 2 gives us:
m = 218
To solve for the number of sociology textbooks, we can substitute into either of our original equations.
m + 41 = s
(218) + 41 = s
s = 259
Therefore, your answer is m = 218 and s = 259, or 218 math textbooks and 259 sociology textbooks were sold.
Hope this helps!
First of all, the modular inverse of n modulo k can only exist if GCD(n, k) = 1.
We have
130 = 2 • 5 • 13
231 = 3 • 7 • 11
so n must be free of 2, 3, 5, 7, 11, and 13, which are the first six primes. It follows that n = 17 must the least integer that satisfies the conditions.
To verify the claim, we try to solve the system of congruences
Use the Euclidean algorithm to express 1 as a linear combination of 130 and 17:
130 = 7 • 17 + 11
17 = 1 • 11 + 6
11 = 1 • 6 + 5
6 = 1 • 5 + 1
⇒ 1 = 23 • 17 - 3 • 130
Then
23 • 17 - 3 • 130 ≡ 23 • 17 ≡ 1 (mod 130)
so that x = 23.
Repeat for 231 and 17:
231 = 13 • 17 + 10
17 = 1 • 10 + 7
10 = 1 • 7 + 3
7 = 2 • 3 + 1
⇒ 1 = 68 • 17 - 5 • 231
Then
68 • 17 - 5 • 231 ≡ = 68 • 17 ≡ 1 (mod 231)
so that y = 68.
Answer:
The answer I have to say would be D. Please correct me if I am wrong but I am positive with my answer!
Step-by-step explanation:
Answer:
Subtract 21 from the left side and add 21 to the right side of the equation.
The answer is b = 198.
Check the solution by substituting 198 for b.
Step-by-step explanation:
