Answer:
see the attachment photo!
The mistake is n third line - adding 3w
96 + 2w =2(80 - 3w)
96 + 2w = 160 - 6w
+ 6w + 6w
96 + 8w = 160
- 96 -96
8w = 64
w = 8 weeks answer
There are 3 questions and 4 choices.
So she has 1/4 of a chance of getting each question right.
Now if you multiply all her odds 1/4 x 1/4 it would become 1/16. Therefore she has 1/16 of a chance of getting a 2/3

The highest common factor is usually reserved for two or more numbers. The HFC of a single number is, trivially, just the number itself.
Mean is 11.3 and the range is 4. Dont need to add 5 for all. Just do mean for the given options and add 5 at the end. Same with the range 9-5=4. Doesn’t change when you add 5 for all
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