Learning Mathematical Variables

The total amount Shobie paid for two kilos of beef and three kilos of fish is less than 𝑃ℎ𝑝 700. Suppose a kilo of beef costs 𝑃ℎ𝑝 250. What what will be the maximum cost of a kilo of fish? Round –off the answer to a whole number.

• 𝑃ℎ𝑝 50

• 𝑃ℎ𝑝 65

• 𝑃ℎ𝑝 66

• 𝑃ℎ𝑝 67

SMJK JIT SIN II holds a charity concert in a hall. Two types of concert ticket, VIP and Special, will be sold among parents. The number of VIP ticket sold is x and the number of Special ticket sold is y. The hall can provide not more that 1000 seats. The number of Special tickets must exceed twice the number of VIP tickets.

A handicraft factory produces x units of hats and y units of baskets everyday. The number of hats produced is not more than 50 units per day. The total production is at least 150 units a day. The number of baskets is not more than two times the number of hats produced.

A fruit grower grows x mango trees and y durian trees in his orchard based on the following constraints.

I : The number of mango trees is less than the number of durian trees.

II : The total number of trees should be more than 50.

III : The number of durian trees is at most three times the number of mango trees.

The following expressions are examples of linear inequalities in two variables EXCEPT:

• – 𝑥 > 2𝑦 + 7

• 9𝑥 + 3𝑦 ≥ 24

• 13𝑥 − 4𝑦 = 21

• 13𝑥 − 24𝑦 < 32

Which of the following verbal phrases DOES NOT represent a linear inequality in two variables?

• “the total number of male and female students in the learning center is less than or equal to 20”

• “the total number of male and female students in the learning center is greater than 20”

• “the total number of male and female students in the learning center is at most 20”

• “the total number of male and female students in the learning center is 20”

Which of the following verbal phrases DOES NOT represent a linear inequality in two variables?

• "the number of students in the learning center is 20"

• "the number of students in the learning center is at most 20"

• "the number of students in the learning center is greater than 20"

• "the number of students in the learning center is less than or equal to 20"

Which inequality represents "the sum of x and y is at most 15"?

By which condition does the inequality symbol of a linear inequality in two variables reverses its directions?

• adding or subtracting negative real numbers

• adding or subtracting positive real numbers

• multiplying or dividing positive real numbers

• multiplying or dividing negative real numbers

James is asked what inequality symbol to be used to translate at most in the mathematical sentence 5 times a number y plus 2 times a number x is at most 15. His answer is <. Is he correct?