JAMB Mathematics 2024 Paper

Concept:Subtraction in base seven involves borrowing in groups of seven, just as base ten uses groups of ten.Explanation:Arrange the numbers under the correct place values.Subtract from the rightmost digit: $5_{\text{seven}} - 6_{\text{seven}}$ requires borrowing, so the next digit $4$ becomes $3$, and $5$ becomes $5 + 7 = 12$. Then $12 - 6 = 6$.Next, $3_{\text{seven}} - 5_{\text{seven}}$ requires borrowing from the far left because the middle places are zero. After carrying, the result in that place is $5$.Continue subtracting each place in base seven: $6 - 2 = 4$, then $6 - 4 = 2$.The leftmost borrow leaves $1 - 1 = 0$, so the leading zero is dropped.Answer:$20045_{\text{seven}} - 14256_{\text{seven}} = 2456_{\text{seven}}$The correct option is B.