5. Seven × a number (n) plus eight is thirty-six. What is the number n?
Answer: C
The number n is 4.
To solve the equation, we set up the expression: 7n + 8 = 36. By isolating n, we find that n equals 4, making it the correct solution.
A) 6.3
This option is incorrect because substituting n = 6.3 into the equation gives 7(6.3) + 8 = 44.1, which does not equal 36. Therefore, 6.3 cannot be the solution for n.
B) 5.4
This option is also incorrect. If we substitute n = 5.4 into the original equation, we calculate 7(5.4) + 8 = 46.8, which is far greater than 36. Hence, 5.4 is not the correct answer.
C) 4
This option is correct. By substituting n = 4 into the equation, we find that 7(4) + 8 = 28 + 8 = 36, which satisfies the equation perfectly. Thus, n equals 4.
D) 3.6
This option is incorrect. If we plug in n = 3.6 into the equation, we get 7(3.6) + 8 = 25.2 + 8 = 33.2, which does not equal 36. Therefore, 3.6 is not the solution.
Conclusion
The correct answer is 4, as it satisfies the equation 7n + 8 = 36. All other options fail to meet the condition of the equation, demonstrating that they cannot be the correct value for n. Thus, option C is definitively the right answer.