@meenu05 said:@iLoveTorres yes can you explain it ?
duplicate ratio means (a+x)^2/(b+x)^2=a/b. then its jus simple solving. hope its clear
@scrabbler can u explain me from where this 200 came into the picture as no. of total students is only 100.
How many perfect squares are of the type ab0ab?
QQQQQ
Rekha Drew a circle of radius 2 cm, on a graph paper of grid 1cm x 1cm
She then calculated the area of circle by adding up only the number of full unit sqares that fall within the perimeter of the circle. If the value that rekha obtained was d^2 cm Less than the correct value. then find the minimum possible value of d ??
a. 4.56
b. 5.56
c. 6.56
d. 3.56
b. 5.56
c. 6.56
d. 3.56
OA -- 5.56
Approach !!??????b
QQQQQ
Rekha Drew a circle of radius 2 cm, on a graph paper of grid 1cm x 1cm
She then calculated the area of circle by adding up only the number of full unit sqares that fall within the perimeter of the circle. If the value that rekha obtained was d^2 cm Less than the correct value. then find the minimum possible value of d ??
a. 4.56
b. 5.56
c. 6.56
d. 3.56
b. 5.56
c. 6.56
d. 3.56
OA -- 5.56
Approach !!??????b
@meenu05 said:if a:b is the duplicate ratio of ( a+ x ) : ( b+x) . then what is the value of x ?
(a+x)^2 / (b+x)^2 = (a/b)
=> (a+x) / (b+x) = √(a/b)
=> x(√a-√b) = a√b - b√a
=> x = √(ab)
=> (a+x) / (b+x) = √(a/b)
=> x(√a-√b) = a√b - b√a
=> x = √(ab)
@ananyboss said:QQQQQRekha Drew a circle of radius 2 cm, on a graph paper of grid 1cm x 1cm She then calculated the area of circle by adding up only the number of full unit sqares that fall within the perimeter of the circle. If the value that rekha obtained was d^2 cm Less than the correct value. then find the minimum possible value of d ??a. 4.56b. 5.56c. 6.56d. 3.56OA -- 5.56Approach !!??????b
Is it d^2 cm or d sq.cm.??
@Pratiyush said:@scrabbler can u explain me from where this 200 came into the picture as no. of total students is only 100.
Suppose we have 225 chocolates and have to distribute them among 100 people so that no-one gets more than 3. What is the minimum number of people who will get 3?
If we try to distribute as evenly as possible, give everyone 2 chocolates, there will still be 25 chocs left and hence 25 people (minimum) will get 3. Pigeonhole principle is the fancy name for this concept.
The situation is similar, if I say out of 100 people there are 85 liking game A, 78 liking B and 71 liking C (for example) then I am distributing 85 + 78 + 71 = 234 likes among 100 people such that no-one can like more than 3. So the pigeonhole principle tells us that a minimum o 234 - 200 = 34 people like all 3.
regards
scrabbler
If we try to distribute as evenly as possible, give everyone 2 chocolates, there will still be 25 chocs left and hence 25 people (minimum) will get 3. Pigeonhole principle is the fancy name for this concept.
The situation is similar, if I say out of 100 people there are 85 liking game A, 78 liking B and 71 liking C (for example) then I am distributing 85 + 78 + 71 = 234 likes among 100 people such that no-one can like more than 3. So the pigeonhole principle tells us that a minimum o 234 - 200 = 34 people like all 3.
regards
scrabbler
@Exodia said:There are two qualities of milk- Amul and Sudha having different prices per litre, their volumes being 130L and 180L respectively. After equal amounts of milk was removed from both, the milk removed from Amul was added to Sudha and vice versa. The resulting two types of milk now have the same price. Find the amount of milk drawn out from each type of milk.1) 58.662) 75.483) 81.234) None of thesePlz give answer alongwith explanation
@sbharadwaj @iLoveTorres
I get 75.48 by doing 130 x 180 /310.
My logic is thus:
Initially there is 130 of type A and 180 of type B so the TOTAL 310 L milk has A and B in the ratio of 130 : 180. Hence if the two cans each have same price both must be in the same ratio and that ratio must be 130 : 180. Hence the amount exchanged must be (130/310) * 180 [or if you prefer, (180/310) * 130]
We can do it with equations too but I am too lazy to use equations...;)
regards
scrabbler
I get 75.48 by doing 130 x 180 /310.
My logic is thus:
Initially there is 130 of type A and 180 of type B so the TOTAL 310 L milk has A and B in the ratio of 130 : 180. Hence if the two cans each have same price both must be in the same ratio and that ratio must be 130 : 180. Hence the amount exchanged must be (130/310) * 180 [or if you prefer, (180/310) * 130]
We can do it with equations too but I am too lazy to use equations...;)
regards
scrabbler
How many four-digit numbers can be made by using exactly three different digits among the digits 4, 5, 6 and 7?
@IIMAIM said:How many four-digit numbers can be made by using exactly three different digits among the digits 4, 5, 6 and 7?
144?
Number of ways of choosing which digits to choose is 4 (repeated digit) x 3C2 (other 2 digits) = 12. Number of ways of arranging chosen digits is 4!/2 = 12. Hence 144.
regards
scrabbler
Number of ways of choosing which digits to choose is 4 (repeated digit) x 3C2 (other 2 digits) = 12. Number of ways of arranging chosen digits is 4!/2 = 12. Hence 144.
regards
scrabbler
@IIMAIM said:How many four-digit numbers can be made by using exactly three different digits among the digits 4, 5, 6 and 7?
4C3*3C1*4!/2! =144
@ananyboss said:QQQQQRekha Drew a circle of radius 2 cm, on a graph paper of grid 1cm x 1cm She then calculated the area of circle by adding up only the number of full unit sqares that fall within the perimeter of the circle. If the value that rekha obtained was d^2 cm Less than the correct value. then find the minimum possible value of d ??a. 4.56b. 5.56c. 6.56d. 3.56OA -- 5.56Approach !!??????b
Should be d cm^2. Then we need to just struggle to see how many unit squares in a gridwe can fit in a circle of radius 2 and hence area 4pi = 12.56 (6 is easy, in 2 rows of 3 each, and if we add one more above the middle one of the upper row we need to check if it still fits in there. If so, then 12.56 - 7 would give the required answer!)
regards
scrabbler
regards
scrabbler
@IIMAIM said:How many four-digit numbers can be made by using exactly three different digits among the digits 4, 5, 6 and 7?
144
The manufacturer of a certain item can sell all he can produce at the selling price of Rs. 60 each. If costs him Rs. 40 in materials and labour to produce each item and he has overhead expenses of Rs. 3000 per week in order to operate the plant. The number of units he should produce and sell in order to make a profit of at least Rs. 1000 per week, is:
a] 400 b] 300 c] 250 d] 200
a] 400 b] 300 c] 250 d] 200
@scrabbler said:Should be d cm^2. Then we need to just struggle to see how many unit squares in a gridwe can fit in a circle of radius 2 and hence area 4pi = 12.56 (6 is easy, in 2 rows of 3 each, and if we add one more above the middle one of the upper row we need to check if it still fits in there. If so, then 12.56 - 7 would give the required answer!)regardsscrabbler
Oops..got it.! Thanks
@Faruq said:The manufacturer of a certain item can sell all he can produce at the selling price of Rs. 60 each. If costs him Rs. 40 in materials and labour to produce each item and he has overhead expenses of Rs. 3000 per week in order to operate the plant. The number of units he should produce and sell in order to make a profit of at least Rs. 1000 per week, is: a] 400 b] 300 c] 250 d] 200
200?
regards
scrabbler
regards
scrabbler
@Faruq said:The manufacturer of a certain item can sell all he can produce at the selling price of Rs. 60 each. If costs him Rs. 40 in materials and labour to produce each item and he has overhead expenses of Rs. 3000 per week in order to operate the plant. The number of units he should produce and sell in order to make a profit of at least Rs. 1000 per week, is: a] 400 b] 300 c] 250 d] 200
200 right.?
SP - CP = profit
60x - ( 40x + 2000 ) = 1000
x = 200
@Faruq said:The manufacturer of a certain item can sell all he can produce at the selling price of Rs. 60 each. If costs him Rs. 40 in materials and labour to produce each item and he has overhead expenses of Rs. 3000 per week in order to operate the plant. The number of units he should produce and sell in order to make a profit of at least Rs. 1000 per week, is: a] 400 b] 300 c] 250 d] 200
60x-40x-3000=1000
x=200