CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Mohan saves Rs. $$1$$ on the first day, Rs. $$2$$ on the second day, Rs. $$3$$ on the third day and so on. What will be his total saving after $$40$$ days?


Solution

Mohan's savings are Rs. $$1$$, Rs. $$2$$, Rs. $$3$$,.... 
Here, $${ t }_{ 1 }=1$$, $$n=40$$
Therefore, $${ t }_{ n }={ t }_{ 40 }=20$$; $${ S }_{ n }={ S }_{ 40 }=$$?
$$\Rightarrow { S }_{ n }=\dfrac { n }{ 2 } \left( { t }_{ 1 }+{ t }_{ n } \right)$$
$$\Rightarrow  { S }_{ 40 }=\dfrac { 40 }{ 2 } \left( 1+40 \right)$$
$$ \Rightarrow { S }_{ 40 }=\dfrac { 40 }{ 2 } \times 41=820$$
Hence, Mohan's total savings after $$40$$ days will be Rs. $$820$$.

Mathematics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image