Number System Questions and Answers

The verified answer is 484, option B. For “Find the square of 22”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 22² = 484.. The distractors 490, 486, 488 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value. An independent reverse-check again gives 484.

The verified answer is 144, option C. For “Which number is divisible by 18?”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 144 divisible by 2 and 9.. The distractors 146, 147, 145 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value.

Translate the statement into integer, fraction or place-value relations and simplify systematically. For “Find the value of 300 ÷ 5”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 300/5 = 60.. The distractors 55, 65, 50 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value.

For “Which number is divisible by 7?”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation.

For “Find the square root of 225”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: √225 = 15..

The verified answer is 175, option D. For “Which number is divisible by 25?”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The distractors 180, 190, 150 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value. An independent reverse-check again gives 175.

For “Find the cube of 7”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 7³ = 343.. The distractors 443, 543, 243 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value. An independent reverse-check again gives 343.

For “Which number is divisible by 15?”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 45 divisible by 3 and 5..

The verified answer is 225, option D. Translate the statement into integer, fraction or place-value relations and simplify systematically. For “Find the value of 15 × 15”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation. The question-specific working recorded with the item is: 15² = 225.. The distractors 235, 200, 210 may arise from changing the order of operations, mishandling a negative sign, using an incorrect reciprocal, ignoring a divisibility condition, or rounding an exact value. An independent reverse-check again gives 225.

For “Which number is a multiple of 9?”, retain the exact signs, brackets, powers and numerical conditions before beginning the calculation.