Let n = cost of 1 notebook
Let p = cost of 1 pencil
Then,
3n + 4p = 8.5
5n + 8p = 14.5
You can solve for one variable in terms of the other and then substitute into the remaining equation.
3n + 4p = 8.5
+ 5n + 8p = 14.5
Multiply the top equation by -2 so that the p-containing terms cancel each other out:
-2(3n + 4p = 8.5)
+ 5n + 8p = 14.5
-n + 0 = -2.5
So after dividing both sides by -1, we see that n = $2.5. Plugging into the first equation gives p = $0.25.
3n + 4p = 8.5
5n + 8p = 14.5
Answer:
more than 15.40 cm and less than 14.60 cm
Step-by-step explanation:
A manufacturer of bolts has a quality control policy that requires it destroy any bolts that are more than 4 standard deviations from the mean.
mean length= 15 cm
standard deviation= 0.10 cm
4 standard deviation from mean= 15±(4×0.10)
therefore, bolts of length more than 15+0.4, and less than 15-0.4 will be destroyed
= 15.40 cm and 14.60 cm
Answer:
x= -5/3 y-5
Step-by-step explanation:
Answer:
182 children, 91 adults, 60 students
Step-by-step explanation:
The quantity of adults is x, then the quantity of children are 2x, the quantity of students is 333-x-2x=333-3x. The charge from all adults is 12x, students gave 7*(333-3x), children gave 5*2x=10x, the sum of all money is 2422
12x+ 7(333-3x)+10x=2422
12x+2331-21x+10x=2422
2331+x=2422
x=91- the amount of adults
1) 91*2=182- the amount of children
333-91-182= 60- the amount of students
No. 1/4 of an hour is 15 minutes..
15 minutes read every day for 15 days is 225 minutes, which is less than 500
