Answer:
Part 1) 

Part 2) 

Part 3) 

Explanation:
The question in English is
Expressed in algebraic language. 
Symbolically write the following expressions: 
Three times a number: 
Four times a number: 
Two-thirds of a number
Let
n ----> the number
Part 1) we have
 Three times a number: 
we know that
The algebraic expression is equal to multiply 3 by the number n
so

Part 2) we have
 Four times a number: 
we know that
The algebraic expression is equal to multiply 4 by the number n
so

Part 3) we have
Two-thirds of a number
we know that
The algebraic expression is equal to multiply the fraction 2/3 by the number n
so
