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Regular gasoline was utilized by $88$percent of the vehicles, with midgrade gas purchased by$2\%$ and premium gas purchased by $10\%$ Regular gas is bought with a credit card $28\%$ of the time, midgrade gas is bought with a credit card $34\%$ of the time, and premium gas is bought with a credit card $42\%$of the time.

Conditional probability: $P(Aâˆ\copyright B)=P(A/B)×P\left(B\right)$

The tree diagram is shown below, according to the question:

Now, for each type of gasoline, determine the likelihood of paying using a credit card.

$P(Regularâˆ\copyright Creditcard)=P(Creditcard/Regular)×P\left(Regular\right)=88\%×28\%=0.88×0.28=0.2464$

$$\begin{gathered} P(Midgradeâˆ\copyright Creditcard)=P(Creditcard/Midgrade)×P\left(Midgrade\right) \\ =2\%×34\% \\ =0.02×0.34=0.0068 \end{gathered}$$

$$\begin{gathered} P(Premiumâˆ\copyright Creditcard)=P(Creditcard/Premium)×P\left(Premium\right) \\ =10\%×42\% \\ =0.10×0.42 \\ =0.042 \end{gathered}$$

Fill in the blanks with the corresponding probabilities:

As a result, the likelihood of the buyer paying using a credit card is $0.2952\%$