21. Rs. 1000 is lent out in two parts, one at 6% simple interest and the other at 8% simple interest. The yearly income is Rs. 75. The sum lent at 8% is-

(a) Rs. 250

(b) Rs. 500

(c) Rs. 750

(d) Rs. 600

22. A jar full of whisky contains 40% of alcohol. A part of this whisky is replaced by another containing 19% alcohol and now the percentage of alcohol was found to be 26. The quantity of whisky replaced is –

(a) 2/5

(b) 1/3

(c) 2/3

(d) 3/5

23. The ratio of milk and water in 66 kg of adulterated milk is 5 : 1. Water is added to it to make to ratio 5 : 3. The quantity of water added is –

(a) 22 kg

(b) 24.75 kg

(c) 16.5 kg

(d) 20 kg

24. Some amount out of Rs. 7000 was lent at 6% p.a. and the remaining at 4% p.a. If the total simple interest from both the fractions in 5 years was Rs. 1600. The sum lent at 6% p.a. was –

(a) Rs. 2000

(b) Rs. 5000

(c) Rs. 3500

(d) none of these

25. A lump of two metals weighing 18 grams is worth Rs 74 but if there weights be interchanged, it would be worth Rs. 60 and 10 paise. If the price of one metal be Rs. 7 and 20 paise per gram, find the weight of the other metal in the mixture?

(a) 6 grams

(b) 8 grams

(c) 12 grams

(d) 14 grams