$149.9 \%$ of $149.9 + 149.9 = ?$

$A$ certain two-digit number is three times the sum of its digits. If $45$ is added to the number,the digits are reversed. Find the number.

$A$ fraction becomes $4$ when $1$ is added to both the numerator and denominator; and it becomes $7$ when $1$ is subtracted from both the numerator and denominator. The numerator of the given fraction is

$958 \times 21 \div 4 = ?$

If in a long division sum,the dividend is $380606$ and the successive remainders from the first to the last are $434, 125,$ and $413,$ then the divisor is:

Two baskets together have $640$ oranges. If $\frac{1}{5}$ of the oranges in the first basket are taken to the second basket,the number of oranges in both baskets becomes equal. The number of oranges in the first basket is: