Pls solve the problem listed below $URGENT$?

Question

A man is employed to count Rs.10710. He count @180 words/minute for half an hour. After this he counts at the rate of Rs. 3 less every prceeding minute{every minute before it}. Find the time taken by the man to count the entire amount?
This question is from RD Sharma Class X Page 5.49 Chapter A.P. Ex. 5.5 Q38

Answer 1

Money counted in half an hour=180*30=Rs.5400

Remaining money=Rs,(10710-5400)
=Rs.5310

after 30 mins

money counted in first min=Rs 177
money counted in 2nd min=Rs 174

here,
a=177
d= -3
s= 5310

we know that
s= n/2*{2a+(n-1)*d}
or,5310=n/2*(354-3n+3)
or,10620=357n-3n^2
or,3n^2-357n+10620=0
or,n^2-119n+3540=0

solving this equation, we have,
n=59 or 60

since in the 60th minute the man counts Rs.0.

so, total time=59+30=89 mins
=1 hour 29 mins

Answer 2

Total count = 10710
Counted in first 1/2 hr = 180 × 30 = 5400
Counting remaining = 10710 – 5400 = 5310
Next counting 177 in 1st minute, then 174 then 171
So the sequence is 177, 174, 171, 168 ----
The total is 177 + 174 + 171 + 168 + ---- = 5310
Sum S = n/2 [2a + (n – 1)d = 5310
a = first count = 177, n = total no. of count, d = common difference = – 3
5310 = n/2[2 × 177 – 3 (n – 1)]
5310 = n/2[354 – 3n + 3]
5310 = n/2[357 – 3n]
3n^2 – 357n + 10620 = 0
n^2 – 119 n + 3540 = 0
n^2 – 59n – 60n + 3540 = 0
n(n – 59) – 60 (n – 59) =0
(n – 59) (n – 60) = 0
Therefore n = 59 or n = 60
Now the sequence is 177, 174, 171, 168 ----,3, 0
Tn = a + (n – 1)d
a = 177 d = – 1 Tn = 3 (Last term) as at that time counting will be completed.
Tn = 3 =177 – 3 n + 3 solving
n = 59 min
Total time required = 59 + 30 = 89 minutes or 1hr 29 min

Answer 3

Ratio = 37:39 enable the full sort of geese be = 37x and entire sort of frogs = 39x => entire sort of geese + entire sort of frogs = 37x + 39x regular = 152 => (37x + 39x) / 2 = 152 => x(37 + 39) / 2 =152 => 38x = 152 => x =4 as a result, sort of geese = 37x = 37 * 4 = 148 and sort of Frogs = 39x = 39 * 4 = 156

Answer 4

89 minutes

Answer 5

If this isn't a problem you need solved because you are in class and need it in order to cheat, then I see no reason why a question of this type can be urgent.
What is the problem are you going to have if you don't find the answer?
IT IS NOT URGENT!

Answer 6

3 hrs

Answer 7

The problem is wrongly worded.

Answer 8

look in the answers page.its so simple.I guess u r an indian.Am i right?

Answer 9

answer is also there on the next page!!!!