Question

a section of a bank statement is shown in the figure. find the mistake that was made by the bank.

Explanation:

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<reasoning>

Verify initial balance and first transaction

Using the Decimal Arithmetic knowledge point
The starting balance is \(\$1083.35\).
On Jan. 2, a payment of \(\$776.32\) is made:
\[
1083.35 - 776.32 = 307.03
\]
The statement balance of \(\$307.03\) is correct.

Verify second transaction

Using the Decimal Arithmetic knowledge point
On Jan. 3, a payment of \(\$39.29\) is made:
\[
307.03 - 39.29 = 267.74
\]
The statement balance of \(\$267.74\) is correct.

Verify third transaction

Using the Decimal Arithmetic knowledge point
On Jan. 4, a deposit of \(\$200.00\) is made:
\[
267.74 + 200.00 = 467.74
\]
The statement balance of \(\$467.74\) is correct.

Verify fourth transaction

Using the Decimal Arithmetic knowledge point
On Jan. 5, a deposit of \(\$1314.21\) is made:
\[
467.74 + 1314.21 = 1781.95
\]
The statement balance of \(\$1781.95\) is correct.

Verify fifth transaction

Using the Decimal Arithmetic knowledge point
On Jan. 6, a withdrawal of \(\$100.00\) is made:
\[
1781.95 - 100.00 = 1681.95
\]
The statement shows a balance of \(\$781.95\).
The bank subtracted \(\$1000.00\) instead of \(\$100.00\).
</reasoning>

<answer>
The mistake made by the bank occurred on Jan. 6. The bank subtracted \(\$1000.00\) instead of \(\$100.00\) for the cash withdrawal, resulting in an incorrect balance of \(\$781.95\) instead of the correct balance of \(\$1681.95\).
</answer>

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Answer:

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<reasoning>

Verify initial balance and first transaction

Using the Decimal Arithmetic knowledge point
The starting balance is \(\$1083.35\).
On Jan. 2, a payment of \(\$776.32\) is made:
\[
1083.35 - 776.32 = 307.03
\]
The statement balance of \(\$307.03\) is correct.

Verify second transaction

Using the Decimal Arithmetic knowledge point
On Jan. 3, a payment of \(\$39.29\) is made:
\[
307.03 - 39.29 = 267.74
\]
The statement balance of \(\$267.74\) is correct.

Verify third transaction

Using the Decimal Arithmetic knowledge point
On Jan. 4, a deposit of \(\$200.00\) is made:
\[
267.74 + 200.00 = 467.74
\]
The statement balance of \(\$467.74\) is correct.

Verify fourth transaction

Using the Decimal Arithmetic knowledge point
On Jan. 5, a deposit of \(\$1314.21\) is made:
\[
467.74 + 1314.21 = 1781.95
\]
The statement balance of \(\$1781.95\) is correct.

Verify fifth transaction

Using the Decimal Arithmetic knowledge point
On Jan. 6, a withdrawal of \(\$100.00\) is made:
\[
1781.95 - 100.00 = 1681.95
\]
The statement shows a balance of \(\$781.95\).
The bank subtracted \(\$1000.00\) instead of \(\$100.00\).
</reasoning>

<answer>
The mistake made by the bank occurred on Jan. 6. The bank subtracted \(\$1000.00\) instead of \(\$100.00\) for the cash withdrawal, resulting in an incorrect balance of \(\$781.95\) instead of the correct balance of \(\$1681.95\).
</answer>

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