What is the Sum of First 70 Odd Numbers?
What is the Sum of First 70 Odd Numbers?
A. 4900
B. 4970
C. 4960
D. None of these
Similar Posts
A steamer goes downstream from one port to another in 4 hours, it covers the same distance upstream in 5 hours. If the speed of the stream is 2km/hr,the distance between the two parts is_______?
A steamer goes downstream from one port to another in 4 hours, it covers the same distance upstream in 5 hours. If the speed of the stream is 2km/hr,the distance between the two parts is_______?A. 50km
B. 60km
C. 70km
D. 80 km
Explanation:
Let the distance between the two parts be x km.
Then speed downstream = x/4 km/hr.
Speed Upstream = x/5 km/hr
Speed of the stream = ½ (x/4 –x/5)
Therefore, ½(x/4 –x/5) = 2. => x/4 –x/5 = 4 => x = 80.
Hence, the distance between the two ports is 80km.The ratio of the radius of two circles is 1: 3, and then the ratio of their areas is_________?
The ratio of the radius of two circles is 1: 3, and then the ratio of their areas is_________?A. 1:3
B. 1:6
C. 1:9
D. 1:5The radius of the two circular fields is in the ratio 3: 5 the area of the first field is what percent less than the area of the second?
The radius of the two circular fields is in the ratio 3: 5 the area of the first field is what percent less than the area of the second?A. 50%
B. 60%
C. 40%
D. 64%A trader marked the price of a car 20% above the cost price and allowed the purchaser 5% discount on the marked price there by gained Rs.8400. Find the cost price of the car?
A trader marked the price of a car 20% above the cost price and allowed the purchaser 5% discount on the marked price there by gained Rs.8400. Find the cost price of the car?A. Rs.60000
B. Rs.75000
C. Rs.68400
D. Rs.78400The side of a square is increased by 25% then how much % does its area increases?
The side of a square is increased by 25% then how much % does its area increases?A. 52.65
B. 56.25
C. 50.75
D. 42.75If a and b are the roots of the equation x2 – 9x + 20 = 0, find the value of a2 + b2 + ab?
If a and b are the roots of the equation x2 – 9x + 20 = 0, find the value of a2 + b2 + ab?A. -21
B. 1
C. 61
D. 21
Explanation:
a2 + b2 + ab = a2 + b2 + 2ab – ab
i.e., (a + b)2 – ab
from x2 – 9x + 20 = 0, we have
a + b = 9 and ab = 20. Hence the value of required expression (9)2 – 20 = 61.