Question 1050467
Use the monthly payment formula,
{{{M=P(R(1+R)^N)/((1+R)^N-1)}}}
where {{{P=210000}}},
{{{N[1]=30*12=360}}}
{{{N[2]=15*12=180}}}
 and 
{{{R[1]=0.08/12=0.0067}}}
{{{R[2]=0.075/12=0.00625}}}
.
.
.
Using the formula,
{{{M[1]=1502.59}}}
{{{M[2]=1946.73}}}
.
.
.

Total payments multiply the monthly payment by number of periods,
{{{T[1]=1502.59*360=540930.90}}}
{{{T[2]=1946.73*180=350410.67}}}
.
.
.
30 yr - Lower monthly payment but twice as many payments
15 yr - Fewer payments but higher monthly payment