116. The ratio of the common differences of two series in Arithmetic Progression is 4:9. If the ratio of their sums of the first 25 terms of the two series is 4:9, what is the ratio of their sums of the first 75 terms?

117. The number N=49!, that is 49x48x47x....4x3x2x1. How many times can the number N repeatedly be divided by 14 so that no reminder is obtained?

118. Taps A, B, and C are connected to a water tank and the rate of flow of water is 21 litres/hour, 28 litres/hour and 24 litres/hour respectively. Taps A and B fill the tank and tap C empties the tank. If all the three taps are opened simultaneously, the tank gets completely filled in 8 hours. What is the capacity of the tank?

119. The original price of an article is $ 3000. The price is discounted by 20% and then raised by 10%. What is the new price of the article?

120. A person claims to have earned a profit of 10%. But it was found that he had calculated the profit percent on Selling Price instead of Cost Price. What was his actual profit?

124. The length of a chord of a circle at a distance of 5 cm from the centre is 24 cm. What is the diameter of the circle?

125. What is the ratio of the areas of a square of side 6 cm and an equilateral triangle of side 6 cm?

126. The largest possible square is inscribed in a circle of circumeference

121. 4*6*4*4 ( assuming he won't go to the party without his shirt and trousers )
122. Brian takes 45/15 = 3 hrs. In this time D covers 3 x 20 = 60 Kms
123. 40/(Pi-2)

134. The speed of a metro train is 54 kilometers per hour. However, the effective speed after including the time of stoppage at stations is 45 kilometers per hour. How many minutes an hour does the train stop?

135. A cone, hemisphere and cylinder have the same base and the heights of the cone and cylinder are equal to the base radius. What would be the ratio of volumes of the three solids?

136. What is the raminder when

151. Two circles of diamters 74 cm and 40 cm have a common chord of length 24 cm. What is the distance between the centers of the circles?

152.Two complementary angles are such that two times the measure of one is equal to three times the measure of the other. What is the measure of the larger angle?

153. The mean of marks scored by the 100 students in a class was 72. The mean of the marks scored by the 70 boys was 75. What was the mean of the marks scored by the girls?

154. The number of students opting for Information Technology courses decreased by 23%. If the present number of students who opted for Information Technology courses is 1540, what was the original number of students who opted for the said course?

155. An investment triples itself in 30 years at simple interest. What is the rate of simple interest?

156. 76% of the students in a school are boys. If the number of girls is 204, what is the total number of students in the school?

157. A toy train travels on a circular path of radius 250 meters at the rate of 10 kilometers/hour. What is the angle moved with reference to the center of the circle in 9 seconds?

158. If sinA=cosA and A iss acute, what is tanA-cotA equal to?

159. If

171. What is the sum of all odd numbers from 1 to 32?

172. What is the unit digit in the product 207x781x39x94?

173. When a number is divided by 296, the remainder is 75. What would the remainder be when the number is divided by 37?

174. Which is the number nearest to 7671 that is exactly divisible by 38?

175. When two numbers are divided by a certain divisor, they give remainders of 35 and 30 respectively. When the sum of the two numbers is divided by the same divisor, the remainder obtained is 20. What is the divisor?

176. What is the value of y is 1y3y6 is divisible by 11?

177. Which is the largest positive integer which divides all integers of the form n³-n?

178. Which is the biggest even divisor of (2n+1)²-1where n is a natural number?

179. What is  the last digit of

179. you said "for any positive integer n", so this digit must be the digit when n=1.

4.16+1=64+1=65=5(mod 10).
let f(x)2.4^n)^2.
We got that f(1)=4(mod 10).
Let for fixed k f(k)=4(mod 10).
Then, for k+1, we get:
f(k+1)2.4^(k+1))^2=f(k) 4^2
But
f(k) 4^2=4.4^2=64=4(mod 10),
so f(k+1)=4(mod 10).
Then the number is 5.

Well done, krassi_holmz!
Your answers are all correct!

176. What is the value of y is 1y3y6 is divisible by 11?
5.

174. Which is the number nearest to 7671 that is exactly divisible by 38?
7676.

173. When a number is divided by 296, the remainder is 75. What would the remainder be when the number is divided by 37?
x===75 (mod 296),
but 37|296, so:
x===75===1(mod 37)

171. What is the sum of all odd numbers from 1 to 32?
271

170. If 2x-y=4 and x+y=5, what is the value of xy?
2x=4+y
x4+y)/2
(4+y)/2+y=5
4+y+2y=10
3y=6
y=2
x=6/2=3
xy=6