12.5cm Squared times 100mm2 over 1cm2?
1cm=10mm
(1cm)^2=(10mm)^2
$${\mathtt{1}}\left[{{cm}}^{{\mathtt{2}}}\right] = {\mathtt{100}}\left[{{mm}}^{{\mathtt{2}}}\right]$$
I guess you mean 12.5cm Squared is (12.5cm)^2,so the question could represnt as:
$${\frac{{\left({\mathtt{12.5}}{cm}\right)}^{{\mathtt{2}}}{\mathtt{\,\times\,}}{\mathtt{100}}\left[{{mm}}^{{\mathtt{2}}}\right]}{{\mathtt{1}}\left[{{cm}}^{{\mathtt{2}}}\right]}} = {\left({\frac{{\mathtt{25}}}{{\mathtt{2}}{cm}}}\right)}^{{\mathtt{2}}} = {\frac{{\mathtt{625}}}{{\mathtt{4}}}}{\mathtt{\,\times\,}}{{\mathtt{cm}}}^{{\mathtt{2}}} = {\mathtt{156.25}}\left[{{cm}}^{{\mathtt{2}}}\right]$$
12.5cm Squared times 100mm2 over 1cm2?
1cm=10mm
(1cm)^2=(10mm)^2
$${\mathtt{1}}\left[{{cm}}^{{\mathtt{2}}}\right] = {\mathtt{100}}\left[{{mm}}^{{\mathtt{2}}}\right]$$
I guess you mean 12.5cm Squared is (12.5cm)^2,so the question could represnt as:
$${\frac{{\left({\mathtt{12.5}}{cm}\right)}^{{\mathtt{2}}}{\mathtt{\,\times\,}}{\mathtt{100}}\left[{{mm}}^{{\mathtt{2}}}\right]}{{\mathtt{1}}\left[{{cm}}^{{\mathtt{2}}}\right]}} = {\left({\frac{{\mathtt{25}}}{{\mathtt{2}}{cm}}}\right)}^{{\mathtt{2}}} = {\frac{{\mathtt{625}}}{{\mathtt{4}}}}{\mathtt{\,\times\,}}{{\mathtt{cm}}}^{{\mathtt{2}}} = {\mathtt{156.25}}\left[{{cm}}^{{\mathtt{2}}}\right]$$