Question 745071
At a concert, the ratio of adults to children is 3:8.
{{{a/c}}} = {{{3/8}}}
:
 The ratio of girls to boys is 3:4.
{{{g/b}}} = {{{3/4}}}
we know
c = g + b
:
Choose a total, the Least common multiple of (3+8),11; and (3+4),7
LCM = 77
then
a + c = 77
{{{a/c}}} = {{{3/8}}} therefore dividing 77 by 11 is 7, so we have:
3*7 = 21 adults
 and
8*7 = 56 children
then we know
g + b = 56
{{{g/b}}} = {{{3/4}}} therefore dividing 56 by 7 is 8, so we have
3*8 = 24 girls
4*8 = 32 boys
:
therefore adults to girls:
{{{a/g}}} = {{{21/24}}} reduces to {{{7/8}}} is the ratio of adults to girls
:
:
Check out by adding; adults, boys, and girls. 21 + 24 + 32 = 77 total