Fill in the blanks :

(i) If 6 pens cost ₹ 69, then the cost of 16 pens is …………… .

(ii) If 1 dozen eggs cost ₹ 54, then a tray of 30 eggs will cost …………… .

(iii) A worker is paid ₹ 1610 as wages for 14 days. His wages for 30 days will be …………… .

(iv) 25 boxes of 12 ice-cream cups each, cost ₹ 10500. The cost of 15 boxes of 20 ice-cream cups each, will be …………… .

(i) If 6 pens cost ₹ 69, then the cost of 16 pens is ₹ 184.

(ii) If 1 dozen eggs cost ₹ 54, then a tray of 30 eggs will cost ₹ 135.

(iii) A worker is paid ₹ 1610 as wages for 14 days. His wages for 30 days will be ₹ 3450.

(iv) 25 boxes of 12 ice-cream cups each, cost ₹ 10500. The cost of 15 boxes of 20 ice-cream cups each, will be ₹ 10500.

Explaination

(i) Given:

Cost of 6 pens = ₹ 69

Cost of 1 pen = ₹ $\Big( \dfrac{69}{6} \Big) \quad \text{[Less pens, Less cost]}$

Cost of 16 pens = ₹ $\Big( \dfrac{69}{6} \times 16 \Big) \quad \text{[More pens, More cost]}$

= ₹ $\Big( \dfrac{23}{2} \times 16 \Big)$

= ₹ 23 x 8 $\quad$ [Dividing 16 and 2 by 2]

= ₹ 184

(ii) Given:

1 dozen = 12 eggs

Cost of 12 eggs = ₹ 54

Cost of 1 egg = ₹ $\Big( \dfrac{54}{12} \Big) \quad \text{[Less eggs, Less cost]}$

Cost of 30 eggs = ₹ $\Big( \dfrac{54}{12} \times 30 \Big) \quad \text{[More eggs, Less More]}$

= ₹ $\Big( \dfrac{54}{2} \times 5 \Big) \quad \text{[Dividing 30 and 12 by 6]}$

= ₹ 27 x 5 $\quad$ [Dividing 54 and 2 by 2]

= ₹ 135

(iii) Given:

Wages for 14 days = ₹ 1610

Wages for 1 day = ₹ $\Big( \dfrac{1610}{14} \Big) \quad \text{[Less days, Less wages]}$

Wages for 30 days = ₹ $\Big( \dfrac{1610}{14} \times 30 \Big) \quad \text{[More days, More wages]}$

= ₹ 115 x 30 $\quad$ [Dividing 1610 and 14 by 14]

= ₹ 3450

(iv) Given:

Let us find the total number of cups first

25 boxes x 12 cups = 300 cups

Cost of 300 cups = ₹ 10500

Cost of 1 cup = ₹ $\dfrac{10500}{300} = ₹ 35 \quad \text{[Less cups, Less cost]}$

15 boxes x 20 cups = 300 cups

Cost of 300 cups = ₹ 35 x 300 $\quad$ [More cups, More cost]

= ₹ 10500