The least number of minutes used to make calls in this month were 1311 minutes, m ≥ 1311 .
Step-by-step explanation:
Given that monthly fee is $20
Payment for additional time in minutes is charged as $0.55 per minutes
The month call bill is at least $85.55, where m is the number of call minutes used that month. This means ;
m*$0.05 +$20 ≥ $85.55
The inequality to form is;
0.05 m +20 ≥ 85.55
Solving this inequality
0.05 m + 20 ≥ 85.55
0.05 m ≥ 85.55 - 20
0.05 m ≥ 65.55
m ≥ 65.55 / 0.05
m ≥ 1311
The least number of minutes used to make calls in this month were 1311 minutes.
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Inequalities :brainly.com/question/10782172
Keywords : monthly fee, additional charge, per minute, charged, inequality
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(a)
4x + 3y = 23
5x + 2y = 20
(b)
4x + 3y = 23 ⇒ -2(4x + 3y = 23) ⇒ -8x - 6y = -46
5x + 2y = 20 ⇒ 3(5x + 2y = 20) ⇒ 15x + 6y = 60
7x = 14
x = 2
5x + 2y = 20
5(2) + 2y = 20
10 + 2y = 20
2y = 10
y = 5
Answer: biscuit = $2, ice cream = $5