Question

b162b
(9) \

$$\begin{array}{r} 142 \\\\ -\\phantom{0}12 \\end{array}$$

(14) \

$$\begin{array}{r} 242 \\\\ -\\phantom{0}12 \\end{array}$$

(10) \

$$\begin{array}{r} 142 \\\\ -\\phantom{0}15 \\end{array}$$

(15) \

$$\begin{array}{r} 242 \\\\ -\\phantom{0}15 \\end{array}$$

(11) \

$$\begin{array}{r} 142 \\\\ -\\phantom{0}27 \\end{array}$$

(16) \

$$\begin{array}{r} 242 \\\\ -\\phantom{0}27 \\end{array}$$

(12) \

$$\begin{array}{r} 142 \\\\ -\\phantom{0}26 \\end{array}$$

(17) \

$$\begin{array}{r} 242 \\\\ -\\phantom{0}26 \\end{array}$$

(13) \

$$\begin{array}{r} 142 \\\\ -\\phantom{0}38 \\end{array}$$

(18) \

$$\begin{array}{r} 242 \\\\ -\\phantom{0}38 \\end{array}$$

b163a kumon
subtraction of 3-digit numbers 1
subtract.
(1) \

$$\begin{array}{r} 130 \\\\ -\\phantom{0}10 \\end{array}$$

(5) \

$$\begin{array}{r} 230 \\\\ -\\phantom{0}10 \\end{array}$$

(2) \

$$\begin{array}{r} 130 \\\\ -\\phantom{0}30 \\end{array}$$

(6) \

$$\begin{array}{r} 230 \\\\ -\\phantom{0}30 \\end{array}$$

(3)* \

$$\begin{array}{r} 130 \\\\ -\\phantom{0}40 \\end{array}$$

(7) \

$$\begin{array}{r} 230 \\\\ -\\phantom{0}40 \\end{array}$$

(4) \

$$\begin{array}{r} 130 \\\\ -\\phantom{0}60 \\end{array}$$

(8) \

$$\begin{array}{r} 230 \\\\ -\\phantom{0}60 \\end{array}$$

Explanation:

<pre_analysis>
{
"quality": "clear",
"question_count": 18,
"skills_matched": [
"step_cot",
"table_formatter",
"explain_then_answer",
"quick"
],
"needs_drawing": false,
"concepts_used": [
"Column Subtraction",
"Subtraction with Regrouping"
],
"new_concepts": [
"Three-Digit Subtraction"
],
"current_concepts": [
"Column Subtraction",
"Subtraction with Regrouping",
"Three-Digit Subtraction"
]
}
</pre_analysis>

<reasoning>

Calculate column subtraction for page B162b

\[

$$\begin{aligned} (9)\quad &142 - 12 = 130 \\ (10)\quad &142 - 15 = 127 \\ (11)\quad &142 - 27 = 115 \\ (12)\quad &142 - 26 = 116 \\ (13)\quad &142 - 38 = 104 \\ (14)\quad &242 - 12 = 230 \\ (15)\quad &242 - 15 = 227 \\ (16)\quad &242 - 27 = 215 \\ (17)\quad &242 - 26 = 216 \\ (18)\quad &242 - 38 = 204 \end{aligned}$$

\]

Calculate column subtraction for page B163a

\[

$$\begin{aligned} (1)\quad &130 - 10 = 120 \\ (2)\quad &130 - 30 = 100 \\ (3)\quad &130 - 40 = 90 \\ (4)\quad &130 - 60 = 70 \\ (5)\quad &230 - 10 = 220 \\ (6)\quad &230 - 30 = 200 \\ (7)\quad &230 - 40 = 190 \\ (8)\quad &230 - 60 = 170 \end{aligned}$$

\]
</reasoning>

<answer>

No.	Problem	Answer
(10)	\(142 - 15\)	\(127\)
(11)	\(142 - 27\)	\(115\)
(12)	\(142 - 26\)	\(116\)
(13)	\(142 - 38\)	\(104\)
(14)	\(242 - 12\)	\(230\)
(15)	\(242 - 15\)	\(227\)
(16)	\(242 - 27\)	\(215\)
(17)	\(242 - 26\)	\(216\)
(18)	\(242 - 38\)	\(204\)
(1)	\(130 - 10\)	\(120\)
(2)	\(130 - 30\)	\(100\)
(3)	\(130 - 40\)	\(90\)
(4)	\(130 - 60\)	\(70\)
(5)	\(230 - 10\)	\(220\)
(6)	\(230 - 30\)	\(200\)
(7)	\(230 - 40\)	\(190\)
(8)	\(230 - 60\)	\(170\)

</answer>

<post_analysis>
{
"subject": "Mathematics",
"question_type": "Free Response",
"knowledge_point": [
"Mathematics",
"Algebra",
"Three-Digit Subtraction"
]
}
</post_analysis>

Answer:

<pre_analysis>
{
"quality": "clear",
"question_count": 18,
"skills_matched": [
"step_cot",
"table_formatter",
"explain_then_answer",
"quick"
],
"needs_drawing": false,
"concepts_used": [
"Column Subtraction",
"Subtraction with Regrouping"
],
"new_concepts": [
"Three-Digit Subtraction"
],
"current_concepts": [
"Column Subtraction",
"Subtraction with Regrouping",
"Three-Digit Subtraction"
]
}
</pre_analysis>

<reasoning>

Calculate column subtraction for page B162b

\[

$$\begin{aligned} (9)\quad &142 - 12 = 130 \\ (10)\quad &142 - 15 = 127 \\ (11)\quad &142 - 27 = 115 \\ (12)\quad &142 - 26 = 116 \\ (13)\quad &142 - 38 = 104 \\ (14)\quad &242 - 12 = 230 \\ (15)\quad &242 - 15 = 227 \\ (16)\quad &242 - 27 = 215 \\ (17)\quad &242 - 26 = 216 \\ (18)\quad &242 - 38 = 204 \end{aligned}$$

\]

Calculate column subtraction for page B163a

\[

$$\begin{aligned} (1)\quad &130 - 10 = 120 \\ (2)\quad &130 - 30 = 100 \\ (3)\quad &130 - 40 = 90 \\ (4)\quad &130 - 60 = 70 \\ (5)\quad &230 - 10 = 220 \\ (6)\quad &230 - 30 = 200 \\ (7)\quad &230 - 40 = 190 \\ (8)\quad &230 - 60 = 170 \end{aligned}$$

\]
</reasoning>

<answer>

No.	Problem	Answer
(10)	\(142 - 15\)	\(127\)
(11)	\(142 - 27\)	\(115\)
(12)	\(142 - 26\)	\(116\)
(13)	\(142 - 38\)	\(104\)
(14)	\(242 - 12\)	\(230\)
(15)	\(242 - 15\)	\(227\)
(16)	\(242 - 27\)	\(215\)
(17)	\(242 - 26\)	\(216\)
(18)	\(242 - 38\)	\(204\)
(1)	\(130 - 10\)	\(120\)
(2)	\(130 - 30\)	\(100\)
(3)	\(130 - 40\)	\(90\)
(4)	\(130 - 60\)	\(70\)
(5)	\(230 - 10\)	\(220\)
(6)	\(230 - 30\)	\(200\)
(7)	\(230 - 40\)	\(190\)
(8)	\(230 - 60\)	\(170\)

</answer>

<post_analysis>
{
"subject": "Mathematics",
"question_type": "Free Response",
"knowledge_point": [
"Mathematics",
"Algebra",
"Three-Digit Subtraction"
]
}
</post_analysis>