1. The monthly salaries of two persons are in the ratio 3:5. If each of them receives and increase of $20 in the monthly salary, the ratio is altered to 13:21. Find their salaries.

2. The ratio of the prices of two houses was 16:23. Two years later, when the price of the first house had risen by 10% and that of the second by $477, the ratio of their prices became 11:20. Find the original prices of the two houses.

3. If a:b = c:d = 25:15what are the values of ad:bc and a+c:b+d?

4.If

show that

.

5.In mixing tea, 1 kg of tea in every 100 kg is wasted. In what proportion must a dealer mix teas which cost him $24 and $18 per kg respectively so that the cost comes to $20 per kg?