The correct option is
C 189
Number of chocolates gifted by his brother = 135
Number of Swiss chocolates gifted by his sister = 180
Total number of chocolates received as gift = Sum of chocolates gifted by his brother and sister
Let's add 135 and 180 using vertical addition.
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Keep in mind that we are adding like terms only.
The total number of chocolates he received as gift is 315.
It is given that he ate 126 of these chocolates.
To get the total number of chocolates he's left with, we need to subtract the number of chocolates he ate from the total number of chocolates.
Let's subtract 126 from 325 using vertical subtraction.
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Keep in mind that we are subtracting like terms only.
Therefore, the total number of chocolates he is left with is 189.