Can you check these inequalities?
1. Chancellor is saving $15 each week for at least n weeks to buy a skateboard that cost $150. Write an inequality to represent this real life situation.
Ans: 15n >= 150
2. Write an inequality to represent the possible speed allowed fi the current highway speed limit is 70 miles per hour.
Ans: s <= 70
3. Bonnie has to raise $150 or more to go to Summer Swim camp. She has raised $30 so far. Write an inequality to represent the amount of money, m, that Bonnie still needs to raise.
Ans: m + 30 >= 150
4. Solve: 8 > x + 3
Ans: 8 > x + 3
= -3 > x -3
= 5 > x or x < 5
5. Sarah's bank account has less than 7 dollars in it. Wrate a set of at least four values that represents the amount of money she has in her account to make the inequality S < 7 true.
Ans: S = 3, 4, 5, 6
6. Desean's teacher told him that he needed to read more than 30minutes each day. Write an inequality that represents the time he needs to read daily if m represents the number of minutes.
Ans: m > 30
7. Solve 1/3x <= 1
1/3x <= 1
3/1)(1/3x) <= 1 (3/1)
Ans: x <= 3
8. SOlve: 2 <= x-6
+6 +6
Ans: 8 <= x or x>= 8
9. Is the inequality 15 <= x equivalent to x >= 15. Explain.
Ans: They are the same. 15 <= x can be rewritten as x >= 15.
10. Tino's Pizza charges $9 for a cheese pizza. Eileen has $45 to buy pizza for the Spanish class. Write and solve an inequality to find the maximum number of pizzas she can buy.
Ans: 9p <= 45
p = 5 pizzas
4 answers
#4 has the right answer, but I don't like the way you stated your solution
First of all, don't put equal signs in front of each new line when solving.
Youre 2nd last line has no relation to the problem, what happened to the 5 ?
here is how I would write it:
8 > x+3
8-3 > x+3-3
5 > x or x < 5
#5,6 , ok
#7 , your solution looks more complicated than it has to be
(1/3)x ≤ 1
times 3
x ≤ 3 or x ≥ 3
#8 , I sure don't like the line that says:
+6 + 6, I have no idea what that is
my way:
2 ≤ x-6
2+6 ≤ x-6+6
8 ≤ x or x ≥ 8
#9, 10 ok