(3) Some amount is equally distributed among some children. If the number of children exceeds by 10, each of them is given Rs 1 less and if the number of children is less by 15, each of them gets Rs. 3 more. Find the number of children and the total amount given to them.
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Verified answer
Answer:
[tex]\qquad \:\boxed{\begin{aligned}& \qquad \:\sf \: Number\:of\:children=40 \qquad \: \\ \\& \qquad \:\sf \:Total\:amount=Rs \: 200 \end{aligned}} \qquad \: \\ \\ [/tex]
Step-by-step explanation:
Let assume that
Number of children be x.
Share of each student be Rs y.
Total amount = Rs xy
Case :- 1 If the number of children exceeds by 10, each of them is given Rs 1 less.
So,
Number of children = x + 10
Share of each student = Rs (y - 1)
So, Total amount = Rs (x + 10)(y - 1)
Thus,
[tex]\sf \: (x + 10)(y - 1) = xy \\ \\ [/tex]
[tex]\sf \: xy - x + 10y - 10 = xy \\ \\ [/tex]
[tex]\sf \: - x + 10y - 10 = 0 \\ \\ [/tex]
[tex]\sf\implies \sf \: x = 10y - 10 \: \: - - - (1) \\ \\ [/tex]
Case :- 2 if the number of children is less by 15, each of them gets Rs 3 more.
So,
Number of children = x - 15
Share of each student = Rs (y + 3)
So, Total amount = Rs (x - 15)(y + 3)
Thus,
[tex]\sf \: (x - 15)(y + 3) = xy \\ \\ [/tex]
[tex]\sf \: xy + 3x - 15y - 45 = xy \\ \\ [/tex]
[tex]\sf \: 3x - 15y - 45 = 0 \\ \\ [/tex]
[tex]\sf \: 3(x - 5y - 15) = 0 \\ \\ [/tex]
[tex]\sf \: x - 5y - 15= 0 \\ \\ [/tex]
On substituting the value of x from equation (1), we get
[tex]\sf \: 10y - 10 - 5y - 15= 0 \\ \\ [/tex]
[tex]\sf \: 5y - 25= 0 \\ \\ [/tex]
[tex]\sf \: 5y = 25\\ \\ [/tex]
[tex]\sf\implies \sf \: y= 5 \\ \\ [/tex]
On substituting the value of y in equation (1), we get
[tex]\sf \: x = 10 \times 5 - 10 \\ \\ [/tex]
[tex]\sf \: x = 50 - 10 \\ \\ [/tex]
[tex]\sf\implies \sf \: x = 40 \\ \\ [/tex]
Hence,
[tex]\qquad \:\boxed{\begin{aligned}& \qquad \:\sf \: Number\:of\:children=40 \qquad \: \\ \\& \qquad \:\sf \:Total\:amount=Rs \: 200 \end{aligned}} \qquad \: \\ \\ [/tex]
Let assume that
Number of children be x.
Share of each student be Rs y.
Total amount = Rs xy
Case:- 1 If the number of children exceeds by 10, each of them is given Rs 1 less.
So,
Number of children = x + 10
Share of each student = Rs(y - 1)
So, Total amount = Rs(x + 10)(y - 1)
Thus,
(x + 10)(y - 1) = xy
xy - x + 10y - 10 = xy
- x + 10y - 10 = 0
Rightarrow x = 10y - 10 - - - (1)
Case :- 2 if the number of children is less by 15, each of them gets Rs 3 more.
So,
Number of children = x - 15
Share of each student = Rs(y + 3)
So, Total amount = Rs(x - 15)(y + 3)
Thus,
(x - 15)(y + 3) = xy
xy + 3x - 15y - 45 = xy
3x - 15y - 45 = 0
3(x - 5y - 15) = 0
x - 5y - 15 = 0
On substituting the value of x from equation (1), we get
10y - 10 - 5y - 15 = 0
5y - 25 = 0
5y = 25
⇒ y = 5
On substituting the value of y in equation (1), we get
x = 10 × 5 - 10
x = 50 - 10
⇒ x = 40
Hence,
Number of children = 40
Total amount = Rs 200