Question 210896
{{{f}}}= father's age now
{{{d}}}= daughter's age now
{{{f = 4d}}}
{{{f + 6 = 3*(d + 6)}}}
{{{4d + 6 = 3d + 18}}}
{{{d = 12}}}
The daughter is 12 yrs old now
check:
{{{f = 4d}}}
{{{f = 48}}}
{{{f + 6 = 3*(d + 6)}}}
{{{48 + 6 = 3*(12 + 6)}}}
{{{54 = 3*18}}}
{{{54 = 54}}}
OK