Step 1
John's debit card is linked to a checking account and has a balance of $1170.
If John wants to purchase an item with his debit card, the most he can spend is all of the money on the debit card which is $1170.
Therefore, the most he can spend on his debit card is $1170.
Step 2
John has a credit card on which he owes $740. His credit limit is, however, $1850
The most he can spend in purchasing an item will be; $1110
[tex]\begin{gathered} \text{ \$1}850-\text{ his debt}=\text{ \$1850-\$740=\$1110} \\ \text{Note his debt=\$740} \end{gathered}[/tex]Step 3
If an item costs $1200, in order to purchase John must have and be able to spend at least $1200 or more on either or both of the cards.
The most he can spend on his debit card is $1170. This is less than $1200, the cost of the item. Therefore, he cannot use the debit card to make the entire purchase.
The most he can spend on his credit card is $1110. This is less than $1200, the cost of the item. Therefore, he cannot use the credit card to make the entire purchase.
Answer; Neither