The number of chairs Sofia and her grandparents need for the party is 108 for 18 tables.
How to calculate the number of chairs needed for Sofia's party?
To calculate the number of chairs for the party we must take into account the relationship between the number of tables and chairs of 1:6, this means that for each table there are 6 chairs.
According to the above, to know the total number of chairs they need, we must multiply 18 (number of tables) by 6 to know how many chairs are needed.
18 × 6 = 108
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