By setting up a system of equations we can easily solve this problem. Let's denote Jane's working hours with x and Jack's working hours with y. Since they don't want to work more than 65 hours, the first equation is x+y=65. The second equation is 14x+7y=770. By solving this system of equation

, we find that y=20 hours, which is Jack's maximum working hours.
Answer:
see explanation
Step-by-step explanation:
The exponents can only be added if the bases are the same
Here one base is 12 and the other is 11
So the rule of addition is not applicable.
The ? is 1.
7*(9*1)=63
Hope this helps!!
Answer: x=-3
Step-by-step explanation:
First you add 3x+5x cause they are both variables.They equal 8x.
Then you subtract 7x from both sides to get x+17=10
then you subtract 17 from both sides.
you will get x= -3
Hope that helps!
Answer:
Step-by-step explanation:
Given that a friend flips a coin 10 times and observes head 7 times. So he concludes Probability of head =0.1
This is wrong because
i) Just making 10 trials and coming to conclusion is wrong. Trials should be large to get accurate estimate
ii) The way he threw the coin may be biased so differrent persons should flip and get results for larger trials
iii) External influences such as air, any other disturbance is not considered here.
To avoid all these sampling fluctuations number of trials should be increased with different situations and times.