$5.6 \times 12.5 \div 0.5 + 15.5 = ? + 49.5$

The sum of the first $45$ natural numbers is:

The number of times $79$ must be subtracted from $50000$ so that the remainder is $43759$ is:

Two numbers are such that the ratio between them is $3:5;$ but if each is increased by $10,$ the ratio between them becomes $5:7.$ The numbers are

If the sum of two numbers is $33$ and their difference is $15,$ the smaller number is

How many numbers between $150$ and $500$ are divisible by $2, 3,$ and $7$ together?