21). If \(a_{n}= 3 - 4n \), then what is \(a_{1} + a_{2} + a_{3} + ...... + a_{n}\) equal to \( [ 1 + 2 + 3 + ..... + n = \frac{n(n + 1)}{2}]\)
A). -n(4n-3) |
B). -n(2n-1) |
C). -\(n^{2}\) |
D). -n(2n-1) |
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22). A train travels at a speed of 40km/hr and another train at a speed of 20m/s. what is the ration of speed of the first train to that of the second train?
A). 2:01 |
B). 5:09 |
C). 5:03 |
D). 9:05 |
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23). \( \left( x+y\right)\) : \( \left( x-y\right)\)= 3 : 5 and xy = positive imply that
A). \(x \) and \( y\) are both positive |
B). \(x \) and \( y\) are both negative |
C). One of them is positive and one of them is negative |
D). No real solutions for \( x\) and \( y\) exist |
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24). How many pairs of \( X\) and \( Y\) are possible in the number \( 763X4Y2\), if the number is divisible by 9?
A). 8 |
B). 9 |
C). 10 |
D). 11 |
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25). What is the remainder when \( 4^{1012}\) is divided by 7?
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26). What is the highest common facter of \( 2x^{3}\)+\( x^{2}\)-\( x\)-\( 2\) and \( 3x^{3}\)-\( 2x^{2}\)+\( x\)-\( 2\)?
A). \( x-1\) |
B). \( x+1\) |
C). \( 2x+1\) |
D). \( 2x-1\) |
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27). What is the remainder when \( \left( 1235 \times 4523 \times 2451\right)\) is divided by 12?
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28). What is the remainder when \( \left(17^{23} + 23^{23} + 29^{23}\right)\) is divided by 23?
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29). \( p\),\( q\) and r are prime numbers. Such that p< q
A). 1 |
B). 2 |
C). 3 |
D). None of these |
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30). The LCM of two numbers is 90 times their HCF. The sum of DCM and HCF is 1456. If one of the numbers is 160; then what is the other number?
A). 120 |
B). 136 |
C). 144 |
D). 184 |
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