Answer:
10. (x-12) > 15
11. -3n ≤12
12. 400 ≤ 11*h
36.36 hours
13. 500 ≥ 150 + n * 50
14. 275≤ 145 + 80 +c
15. 175≥ 45*n +5n
She can only buy 3 tickets ( no partial tickets)
Explanation:
10. Write the inequality correctly: The difference of x and 12 is more than 15
Difference is subtraction more than is >
(x-12) > 15
11. Write the inequality correctly: The product of -3 and a number is at most 21.
Product is multiplication and at most means ≤
-3n ≤12
12. Wages = hours worked * rate
400 = hours * 11
He wants to make at least 400
400 ≤ 11*h
Divide each side by 11
400/11 ≤h
36.36 hours
13. Total cost = helmet + number of lessons*rate
She can spend no more than 500
500 ≥ 150 + n * 50
14. Total cans = cans first week + cans second week + cans third week
We want 275 cans or more
275≤ 145 + 80 +c
15. Cost of concert = cost of ticket * number of tickets + fee * number of tickets
It cannot cost more than 175
175≥ 45*n +5n ( assuming a service fee per ticket)
Combine like terms
175≥ 45*n +5n
175≥50n
Divide by 50
175/50 ≥50n/50
3.5 ≥ n
She can only buy 3 tickets ( no partial tickets)