mml=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfenced open="[" close="]"><mrow><mfrac><mfenced><mfenced><mrow><mn>70</mn><mo> </mo><mo>-</mo><mo> </mo><mn>63</mn></mrow></mfenced></mfenced><mn>70</mn></mfrac><mo> </mo><mo>×</mo><mo> </mo><mn>100</mn></mrow></mfenced><mo>%</mo><mo> </mo><mo>=</mo><mo> </mo><mfrac><mn>7</mn><mn>70</mn></mfrac></math>