Wednesday, August 21, 2013

algebra

sum of two numbers is 80 and the sum of their reciprocal is 4/75. Find the two numbers.

AP



Find the value of the expression:
(2 + 4 + 6 +.... + 100) + (1 + 3 + 5 + 7 + ...... + 99) ÷ 101

8-indicies



Find the value of k in the expression

64 + 2.64 + 3.64 + 4.64 + 5.64 + ....49.64 = k2

7-indicies



Find the value of x for which a= 2100 + (250)2 + (225)4 + (25)20 and b = 299 + (233)3 + (211)9 + (23)33 +299.x are equal (a = b).


6-indicies



Show that 25n+1.3n+1 – 3n+2.52n+1 + 5n.15n where n is a natural number, is completely divisible by 31.

Numbers




Tuesday, August 20, 2013

numbers

Find the natural number for which 2010n –n2010 = 2009

number and divisibility

Prove that 20 + 21 + 22 + 23 + …. 298 is divisible by 7

5-indicies

Prove that X = 42n+3.32n+3 - 62n+3.22n+1 is a perfect square.

numbers

If n is a Natural number, then show that 7n -3 is divisible by 2.


Numbers

If x and y are digits such that 23xy + xy23 + xyxy = 11413, then find the value of x + y.

4-indicies


If,  (x – 2)2x-4. 23 = 817. Then find the value of x

3-indicies


If A = 22n+1.3n+5, and a = 4n, and b = 3n+4
Express A in terms of a and b.

Simultaneous Equation

At a flower show which 1250 attended, outsiders were charged $1, villagers $ 0.5 and school children $ 0.05. The total receipt from the flower show was $695. There were 3 times as many villagers as outsiders. How many outsiders came to the show?


Simultaneous equation using cross multiplication technique



Use cross multiplication to solve the equation:

5x- 3y -1=0 -------------- (1)
x +2y- 12=0 --------- (2)


simultaneous equation using cross multiplication technique



Use cross multiplication to solve the simultaneous equation:
3x-2y-5=0
4x +6y+12=0


Ratio and proportion



Show that:
If,
                 ax+cy+bz=0 ---- (1)
                 cx+by+az=0 ---- (2)
                 bx+ay+cz=0 ---- (3)

Then, a3+b3+c3 = 3abc
 

Ratio and Proportion

Find the ratio x:y:z from the following set of equation:

ax+by+cz=0
lx+my+nz=0

MAKING THE SUBJECT OF THE EQUATION

 

MAKING THE SUBJECT OF THE EQUATION