Question Detail

What is the largest 4 digit number exactly divisible by 88

9900
9999
9988
9944

Answer: Option D

Explanation:

Largest 4 digit number is 9999
After doing 9999 ÷ 88 we get remainder 55
Hence largest 4 digit number exactly divisible by 88 = 9999 - 55 = 9944

1. 1307 * 1307 = ?

1608249
1508249
1408249
1708249

Answer: Option D

Explanation:

\begin{aligned}
(a + b)^{2} = (a^2 + b^2 + 2ab)
\end{aligned}
\begin{aligned}
1307^{2} = (1300 + 7)^2 = (1690000 + 49 + 18200)
\end{aligned}

2. There are four prime numbers written in ascending order. The product of first three is 385 and that of last three is 1001. The last number is:

Answer: Option B

Explanation:

\begin{aligned} \frac{abc}{bcd} = \frac{385}{1001} => \frac{a}{d} = \frac{5}{13} \end{aligned}So d = 13

3. 469157 * 9999

1691100843
4591100843
4691100843
3691100843

Answer: Option C

Explanation:

469157 * (10000 - 1)
= 4691570000 - 469157
= 4691100843

4. 1939392 * 625

1212120010
1212120000
1212120011
1212121010

Answer: Option B

Explanation:

Trick: when multiplying with \begin{aligned} 5^n
\end{aligned} then put n zeros to the right of multiplicand and divide the number with \begin{aligned} 2^n
\end{aligned}
So using this we can solve this question in much less
time.
\begin{aligned} 1939392 \times 5^4 = \frac {19393920000}{16} = 1212120000
\end{aligned}

5. 7589 - X = 3434

4155
2321
3155
None of above

Answer: Option A