Question 1179646
c = no. with cavities
n = no. without cavities
:
In Bob's class the number of students with cavities is 6 more than the number without cavities.
 c = n + 6
When 1/8 of the number of students with cavities was treated they totalled the same number as the students without cavities.
c - {{{1/8}}}c = n
{{{7/8}}}c = n
get rid of the denominator, mult by 8
7c = 8n
replace c with (n+6)
7(n+6) = = 8n
7n + 42 = 8n
42 = 8n - 7n
42 = n
:
How many students of the original group have cavities and do not have cavities respectively.
n = 42 do not have have cavities
and
42 + 6 = 48 had cavities originally
:
:
Check
{{{7/8}}}(48) = 42