Question

answer the following multiple choice questions: (1 mark each)
what is the gcf of 12 and 66?
a. 13
b. 1
c. 6
d. 11
e. 3
what is the gcf of 39 and 52?
a. 1
b. 26
c. 13
d. 1
e. 11
what is the value of 5×3 - 12+(4 + 8)?
a. 0
b. 10
c. 14
d. 9
e. 13
6 + 6×6 - 6=
a. 36
b. 84
c. 74
d. 18
e. 6
what is the value of 7^1
a. 7
b. 14
c. 21
d. 0
e. 28

Explanation:

Step1: Find GCF of 12 and 66

Prime - factorize: \(12 = 2\times2\times3\), \(66=2\times3\times11\). The common factors are 2 and 3, so \(GCF(12,66)=2\times3 = 6\).

Step2: Find GCF of 39 and 52

Prime - factorize: \(39 = 3\times13\), \(52 = 2\times2\times13\). The common factor is 13, so \(GCF(39,52)=13\).

Step3: Calculate \(5\times3−12+(4 + 8)\)

First, calculate the sum in the parentheses: \(4 + 8=12\). Then, \(5\times3=15\). The expression becomes \(15−12 + 12=15\). (There seems to be a calculation error in the original work as the correct order of operations is used here).

Step4: Calculate \(6+6\times6−6\)

According to the order of operations (multiplication first), \(6\times6 = 36\). Then \(6+36−6=36\).

Step5: Calculate \(7^1\)

By the definition of exponents, \(a^1=a\), so \(7^1 = 7\).

Answer:

1. C. 6
2. C. 13
3. (There is an error in the original options as the correct answer is 15)
4. A. 36
5. A. 7