all baout number

hurm aq mang da agak da... law pogram marketing akn peni ngn nombor ga pada akhir nyeww at klass td aq stdy usiness mathematic ,,, that question is look simple p law  pandang btol2 law x bace btol2 jawapan yg akn kite dpt t sala .. hurm dgn perasaan gram dan x puas ahty terhadap diri sendr i'm going to meet my lecture Mdn Yati , i ask my lect y i can't get the true answer although i use a true formula ... my lect juz give me a simple smile then show me how to calculate the question ... hurm lame ga tenung question uw akhir nyew br aq paham upe nye aq sala tekan at calculater haiyaaa..... tu la dye cite aq at class ari nie