For Velma to learn the least number of characters on Saturday, she needs to learn the maximum number on the rest of the days. Make a table of days and fill with characters learned each day to avoid any confusion.
Sun = 12
Mon = 12
Tue = 12
Wed = 12
Thu = 12
Fri = 4
Sat = ?
Total = 71
Now, try to solve yourself before looking at the complete solution.
Complete step-by-step solution:
Total number of characters to be learned = 71
Let the number of characters leaned by Velma on Saturday be x.
Number of characters learned on Friday = 4
Number of characters learned on any other day = 12 (a dozen)
Total number of such days where Velma learns 12 characters = 5
The sum of characters learned on each day should be equal to 71
Which mean that 12+12+12+12+12+4+x = 71
=> x = 71-64 = 7.
Hence, Velma needs to learn at least 7 Japanese hiragana characters on Saturday. Option (C)
1) 1 Dozen = 12 items
2) The most common mistake that one can make here is to forget Sunday. In that case you come up with the answer 19.