Let's solve this step by step.

1. Define Variables:

   • Let the cost of the juice be $x$ dollars.
   • The cost of one donut is $x + 0.40$ dollars (since it's 40 cents more than the juice).

2. Write the Equation:

   • Tammie bought 2 donuts and 1 juice, and she paid $5. Therefore, we can write the equation: $2(x + 0.40) + x = 5$

3. Solve the Equation:

   • Expand and combine like terms: $2x + 0.80 + x = 5$ $3x + 0.80 = 5$
   • Subtract 0.80 from both sides: $3x = 4.20$
   • Divide by 3: $x = 1.40$

   The juice costs $1.40. Therefore, the cost of one donut is: $x + 0.40 = 1.40 + 0.40 = 1.80$

So, one donut costs:

• Dollar amount: $1
• Cent amount: 80 cents

Would you like further details or have any questions?

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Here are 5 related questions to expand your understanding:

1. What would be the cost of the juice if the total bill was $4.60?
2. If Tammie bought 3 donuts and 2 juices for $8.60, what would the cost of one donut be?
3. How much would Tammie pay if the juice was 50 cents cheaper than the donut?
4. If the juice price increased by 20 cents, how much would Tammie pay for the same items?
5. How much change would Tammie get if she paid with a $10 bill?

Tip: When dealing with word problems, carefully translating the conditions into algebraic expressions helps ensure accuracy in solving the problem.