Another Peek Beyond the Point | IT

Question 2

Jonali goes to the market to buy spices. She purchases 50 g of Cinnamon, 100 g of Cumin seeds, 25 g of Cardamom and 250 g of Pepper. Express each of the quantities in kilograms by writing them in terms of fractions as well as decimals.

Solution

We will convert grams to kilograms using the fact that 1 kilogram equals 1000 grams.

Step 1 — Convert Cinnamon quantity

Jonali bought 50 grams of Cinnamon. We know that $1 \text{ g} = \frac{1}{1000} \text{ kg}$ . Let us convert 50 g to kilograms as a fraction.

$50 \text{ g} = 50 \times \frac{1}{1000} \text{ kg}$

$= \frac{50}{1000} \text{ kg}$

$= \frac{5}{100} \text{ kg}$

$= \frac{1}{20} \text{ kg}$

$\boxed{\frac{1}{20} \text{ kg}}$

Now, let us convert 50 g to kilograms as a decimal.

$50 \text{ g} = \frac{50}{1000} \text{ kg}$

$= 0.050 \text{ kg}$

$= 0.05 \text{ kg}$

$\boxed{0.05 \text{ kg}}$

Step 2 — Convert Cumin seeds quantity

Jonali bought 100 grams of Cumin seeds. We will convert 100 g to kilograms as a fraction.

$100 \text{ g} = 100 \times \frac{1}{1000} \text{ kg}$

$= \frac{100}{1000} \text{ kg}$

$= \frac{1}{10} \text{ kg}$

$\boxed{\frac{1}{10} \text{ kg}}$

Next, we will convert 100 g to kilograms as a decimal.

$100 \text{ g} = \frac{100}{1000} \text{ kg}$

$= 0.100 \text{ kg}$

$= 0.1 \text{ kg}$

$\boxed{0.1 \text{ kg}}$

Step 3 — Convert Cardamom quantity

Jonali bought 25 grams of Cardamom. Let us convert 25 g to kilograms as a fraction.

$25 \text{ g} = 25 \times \frac{1}{1000} \text{ kg}$

$= \frac{25}{1000} \text{ kg}$

$= \frac{1}{40} \text{ kg}$

$\boxed{\frac{1}{40} \text{ kg}}$

Now, let us convert 25 g to kilograms as a decimal.

$25 \text{ g} = \frac{25}{1000} \text{ kg}$

$= 0.025 \text{ kg}$

$\boxed{0.025 \text{ kg}}$

Step 4 — Convert Pepper quantity

Jonali bought 250 grams of Pepper. We will convert 250 g to kilograms as a fraction.

$250 \text{ g} = 250 \times \frac{1}{1000} \text{ kg}$

$= \frac{250}{1000} \text{ kg}$

$= \frac{1}{4} \text{ kg}$

$\boxed{\frac{1}{4} \text{ kg}}$

Next, we will convert 250 g to kilograms as a decimal.

$250 \text{ g} = \frac{250}{1000} \text{ kg}$

$= 0.250 \text{ kg}$

$= 0.25 \text{ kg}$

$\boxed{0.25 \text{ kg}}$

Answer

(i) Cinnamon: $\frac{1}{20}$ kg (fraction) and $0.05$ kg (decimal) (ii) Cumin seeds: $\frac{1}{10}$ kg (fraction) and $0.1$ kg (decimal) (iii) Cardamom: $\frac{1}{40}$ kg (fraction) and $0.025$ kg (decimal) (iv) Pepper: $\frac{1}{4}$ kg (fraction) and $0.25$ kg (decimal)

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