Answer:
Total Amount spent on all the cards = $ 42.3
No of cards = 16 .
Step-by-step explanation:
The cost is calculated by multiplying the number of items with their costs. As we have different costs for each card we will add the costs of different cards to get the total costs.
Janet buys 3 postcards for $1.05.
Janet spends 3* $1.05= $ 3.15
Rosie buys five postcards for $1.75
Rosie spends 5 * $ 1.75= $ 8.75
Tanya buys eight postcards for $3.80
Tanya spends 8 * $3.80 = $ 30.4
Total Amount spent on all the cards = $ 3.15+$ 8.75+$ 30.4= $ 42.3
No of cards = 3 + 5+ 8= 16 cards were bought .