If 28 pennies weigh 42 grams, what is the weight in grams of 50 pennies?

Answer

To solve the problem of finding the weight of 50 pennies when 28 pennies weigh 42 grams, we can use the unitary method. Here’s a step-by-step solution:

### Step 1: Find the weight of one penny.
We know that 28 pennies weigh 42 grams. To find the weight of one penny, we divide the total weight by the number of pennies.

\[ \text{Weight of one penny} = \frac{42 \text{ grams}}{28 \text{ pennies}} = \frac{42}{28} = \frac{3}{2} \text{ grams} \]

### Step 2: Calculate the weight of 50 pennies.
Now that we know the weight of one penny is \( \frac{3}{2} \) grams, we can find the weight of 50 pennies by multiplying the weight of one penny by 50.

\[ \text{Weight of 50 pennies} = \left(\frac{3}{2} \text{ grams}\right) \times 50 = \frac{3 \times 50}{2} = \frac{150}{2} = 75 \text{ grams} \]

### Final Answer:
The weight of 50 pennies is **75 grams**.

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