Question Number 203825 by necx122 last updated on 29/Jan/24
$${A}\:{sum}\:{of}\:\mathrm{2800}\:{is}\:{invested},\:{partly}\:{at}\:\mathrm{5\%} \\ $$$${and}\:{partly}\:{at}\:\mathrm{4\%}.\:{If}\:{the}\:{total}\:{income} \\ $$$${is}\:\mathrm{128}\:{per}\:{annum},\:{find}\:{the}\:{amount} \\ $$$${invested}\:{at}\:\mathrm{5\%}. \\ $$
Answered by esmaeil last updated on 29/Jan/24
$${A}+{B}=\mathrm{2800} \\ $$$$\mathrm{0}.\mathrm{05}{A}+.\mathrm{04}{B}=\mathrm{128}\rightarrow \\ $$$$\mathrm{0}.\mathrm{05}×{A}+\mathrm{0}.\mathrm{04}\left(\mathrm{2800}−{A}\right)=\mathrm{128}\rightarrow \\ $$$$\mathrm{0}.\mathrm{01}{A}=\mathrm{16}\rightarrow{A}=\mathrm{1600}\rightarrow \\ $$$${B}=\mathrm{1200} \\ $$$$\rightarrow\mathrm{0}.\mathrm{05}×\mathrm{1600}=\mathrm{80} \\ $$$$ \\ $$
Commented by necx122 last updated on 29/Jan/24
This is great. Thank you.
Commented by esmaeil last updated on 29/Jan/24
$${you}'{re}\:{welcome}. \\ $$