Answer:
B 
Step-by-step explanation:
 
        
             
        
        
        
The answer for this would be x= 38/5
        
                    
             
        
        
        
He had saved 320 initially
Step-by-step explanation:
Let the amount he saved be 'a' 
Amount spent = 20 + 40 + 30
= 90
His grand father gave 50
At the end he has 280
280 = a - 90 +50
a = 280 -50 +90
= 320
He had saved 320 initially
 
        
             
        
        
        
0.2 is the same as 2/10
18/(2/10)
As you may have learned in school, when you divide a fraction, you flip the fraction in the denominator, and change it to multiplication
18/(2/10) becomes 18 x (10/2)
multiply normally
18 x 10 = 180
divide to find answer
180/2 = 90
90 is your answer
hope this helps
Remember, when you meet this problem, flip the second fraction, and change the division sign into multiplication. (always second, never first (if first is a fraction)).