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Question Number 149595 by SLVR last updated on 06/Aug/21
Commented by SLVR last updated on 06/Aug/21
$${sir}\:{solution}\:{please}.. \\ $$
Answered by mr W last updated on 06/Aug/21
$${Q}\mathrm{2} \\ $$$${abcde}×\mathrm{9}={edcba} \\ $$$${a}×\mathrm{90000}+{b}×\mathrm{9000}+{c}×\mathrm{900}+{d}×\mathrm{90}+\mathrm{9}{e} \\ $$$$={e}×\mathrm{10000}+{d}×\mathrm{1000}+{c}×\mathrm{100}+{b}×\mathrm{10}+{a} \\ $$$${a}×\mathrm{8999}+{b}×\mathrm{8990}+{c}×\mathrm{800}−{d}×\mathrm{910}−{e}×\mathrm{9991}=\mathrm{0} \\ $$$${a}×\mathrm{89999}+{b}×\mathrm{8990}+{c}×\mathrm{800}={d}×\mathrm{910}+{e}×\mathrm{9991} \\ $$$$\Rightarrow{a}=\mathrm{1},\:{e}=\mathrm{9}: \\ $$$$\mathrm{80}+{b}×\mathrm{8990}+{c}×\mathrm{800}={d}×\mathrm{910} \\ $$$$\mathrm{8}+{b}×\mathrm{899}+{c}×\mathrm{80}={d}×\mathrm{91} \\ $$$$\Rightarrow{b}=\mathrm{0}: \\ $$$$\mathrm{8}+{c}×\mathrm{80}={d}×\mathrm{91} \\ $$$$\Rightarrow{c}=\mathrm{9}: \\ $$$$\mathrm{8}+\mathrm{720}={d}×\mathrm{91} \\ $$$$\Rightarrow{d}=\mathrm{8} \\ $$$${the}\:{number}\:{is}\:\mathrm{10989}. \\ $$$$\mathrm{10989}×\mathrm{9}=\mathrm{98901} \\ $$$$ \\ $$$$\mathrm{1}+\mathrm{0}+\mathrm{9}+\mathrm{8}+\mathrm{9}=\mathrm{27} \\ $$$$\left.\Rightarrow{answer}\:{B}\right) \\ $$
Answered by mr W last updated on 06/Aug/21
$${Q}\mathrm{1} \\ $$$$\mathrm{4}×\mathrm{4}×\mathrm{3}×\mathrm{2}×\mathrm{1}=\mathrm{96} \\ $$$$\left.\Rightarrow{answer}\:{A}\right) \\ $$
Commented by SLVR last updated on 06/Aug/21
$${Thank}\:{you}\:{so}\:{much}..{mr}.\:{W}\:{sir} \\ $$