Question 1)
Given:
Cost of each shirt = 20$
Cost of each tie = 12$
To find:
An expression for the cost of 's' shirts and 't' ties
Steps:
Number of shirts = 's'
cost of shirts = 20 * s (becuase one shirt cost 20 so n shirts cost 20 * n shirts)
Number of ties = 't'
Cost of ties = 12 * t (becuase one tie cost 12 so n ties cost 12 * n ties)
Total cost = 20 * s + 12 * t
=20s + 12t
Therefore the answer is b) 20s + 12t
Question 2)
We know that 100% = 1
So, 40% = 0.4
Therefore an expression that represnets 40% of a number is 0.4n
So, it B) False
Question 3)
Given:
t = -2
x = 3
z = 5
To find:
4z + 3x - t
Steps:
4z + 3x - t
= 4(5) + 3(3) - (-2)
= 20 + 9 + 2
= 29 + 2
= 31
Therefore the answer is C) 31
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