Question
The average weight of a class of 25 student is 60 KG. If
X is student joined the class, ย than the average weight of whole class increases by (2X โ 7)Kg. Find the value of X if the weight of whole class increases by 390 KG.Solution
Sum of weights of 25 student = 25*60 = 1500 kg Sum of the weights of (25+x)(60+2x-7) = {(25+x)(53+2x)} kg As per the question (25+x)(53+2x)-1500 = 390 (25+x)(53+2x) = 1890 2xยฒ + 103x โ 565 = 0 X= 5 or (-113/2) Student since the number of student cannot be negative. So our answer will be 5.
How many numbers are immediately preceded and succeeded by symbol?
6 7 @ # 2 8 8 $ 5 4 % 5 ! & # * 7 * + 9
If R = 10, RAT = 78, then โRATEโ will be equal to?
Select the option that is related to third number-cluster in the same way first number cluster is related to second number-cluster.
53: 34 :: 6...
268 : 284 :: 429 : ?
Select the option that is related to the fifth number in the same way as the second number is related to first number and the third number is related to...
Select the combination of letter that when sequentially placed in the blanks of the given series will complete the series.
T _ M E _ _ T I _ E R ...
Select the set of numbers that is similar to the following set:
(24, 31, 37)
Select the option in which the numbers are related in the same way as are the numbers in the given set.
(15, 48, 98)
Select the option that is related to fourth number in the same way as the first number is related to the second number and the fifth number is related t...
Select the option that is related to the third number in the same way as the second number is related to the first number.
53: 636 :: 51: ?