Sum of digits = 5 + 1 + 7 + $ x $ + 3 + 2 + 4 = 22 + $ x $, which must be divisible by 3.
$\therefore$ $ x $ = 2.
Sum of digits = (4 + 8 + 1 + x + 6 + 7 + 3) = (29 + x), which must be divisible by 9.
$\therefore$ $ x $ = 7.
Let the number be $ x $ and on dividing $ x $ by 5, we get $ k $ as quotient and 3 as remainder.
$\therefore$ $ x $ = 5k + 3
$\Rightarrow$ $ x $2 = (5k + 3)2
= (25 k 2 + 30$ k $ + 9)
= 5(5 k 2 + 6$ k $ + 1) + 4
$\therefore$On dividing $ x $2 by 5, we get 4 as remainder.
Required numbers are 102, 108, 114, ... , 996
This is an A.P. in which $ a $ = 102, $ d $ = 6 and $ l $ = 996
Let the number of terms be $ n $. Then,
$ a $ + $\left( n - 1\right)$ d = 996
$\Rightarrow$ 102 + $\left( n - 1\right)$ x 6 = 996
$\Rightarrow$ 6 x $\left( n - 1\right)$ = 894
$\Rightarrow$ $\left( n - 1\right)$ = 149
$\Rightarrow$ $ n $ = 150.
Clearly, 4864 is divisible by 4.
So, 9P2 must be divisible by 3. So, 9 + P + 2 must be divisible by 3.
$\therefore$ P = 1.
6) 4456 (742
42
-------
25
24
-------
16
12
--------
4
Therefore, Required number = (6 - 4) = 2.
6 = 3 x 2. Clearly, 5 * 2 is divisible by 2. Replace * by $ x $.
Then, 5 + $x$ + 2 must be divisible by 3. So, $ x $ = 2.
45 = 5 x 9, where 5 and 9 are co-primes.
Unit digit must be 0 or 5 and sum of digits must be divisible by 9.
Among given numbers, such number is 202860.
(325 + 326 + 327 + 328) = 325 x (1 + 3 + 32 + 33) = 325 x 40
= 324 x 3 x 4 x 10
= (324 x 4 x 30), which is divisible by30.
Let the numbers be $ a $ and $ b $. Then, $ a $ + $ b $ = 12 and ab = 35.
$\therefore \dfrac{a + b}{ab} $=$ \dfrac{12}{35} $ $\Rightarrow$ $ \left(\dfrac{1}{b} +\dfrac{1}{a} \right) $=$ \dfrac{12}{35} $
$\therefore$ Sum of reciprocals of given numbers =$ \dfrac{12}{35} $
- Simple Interest Test 3
- Decimal Fraction Test 2
- Decimal Fraction Test 1
- Probability Test 2
- Probability Test 1
- Permutation and Combinations Test 2
- Permutation and Combinations Test 1
- Logarithms Test 2
- Logarithms Test 1
- Time and Distance Test 3
- Time and Distance Test 2
- Time and Distance Test 1
- Compound Interest Test 2
- Compound Interest Test 1
- Divisibility Test 1
- Simple Interest Test 2
- Simple Interest Test 1
- Profit and Loss Test 3
- Profit and Loss Test 2
- Profit and Loss Test 1
- L.C.M and H.C.F Test 3
- L.C.M and H.C.F Test 2
- L.C.M and H.C.F Test 1
- Numbers Test 3
- Numbers Test 2
- Numbers Test 1
- Divisibility Test 3
- Divisibility Test 2