Question

b149a kumon
subtraction of 2-digit numbers 3
subtract
(1) \

$$\begin{array}{r} 73 \\\\ - 22 \\end{array}$$

(5) \

$$\begin{array}{r} 85 \\\\ - 46 \\end{array}$$

(2) \

$$\begin{array}{r} 73 \\\\ - 26 \\end{array}$$

(6) \

$$\begin{array}{r} 85 \\\\ - 53 \\end{array}$$

(3) \

$$\begin{array}{r} 73 \\\\ - 35 \\end{array}$$

(7) \

$$\begin{array}{r} 85 \\\\ - 55 \\end{array}$$

(4) \

$$\begin{array}{r} 73 \\\\ - 37 \\end{array}$$

(8) \

$$\begin{array}{r} 85 \\\\ - 77 \\end{array}$$

Explanation:

<pre_analysis>
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"skills_matched": [
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"table_formatter",
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"quick"
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"concepts_used": [
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"Subtraction with Regrouping"
],
"new_concepts": [],
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"Subtraction with Regrouping"
]
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</pre_analysis>

<reasoning>

Subtract values on page B148b

\[

$$\begin{aligned} (9) \quad 81 - 34 &= 47 \\ (10) \quad 81 - 30 &= 51 \\ (11) \quad 81 - 36 &= 45 \\ (12) \quad 81 - 69 &= 12 \\ (13) \quad 81 - 65 &= 16 \\ (14) \quad 83 - 46 &= 37 \\ (15) \quad 83 - 49 &= 34 \\ (16) \quad 83 - 47 &= 36 \\ (17) \quad 83 - 74 &= 9 \\ (18) \quad 83 - 83 &= 0 \end{aligned}$$

\]

Subtract values on page B149a

\[

$$\begin{aligned} (1) \quad 73 - 22 &= 51 \\ (2) \quad 73 - 26 &= 47 \\ (3) \quad 73 - 35 &= 38 \\ (4) \quad 73 - 37 &= 36 \\ (5) \quad 85 - 46 &= 39 \\ (6) \quad 85 - 53 &= 32 \\ (7) \quad 85 - 55 &= 30 \\ (8) \quad 85 - 77 &= 8 \end{aligned}$$

\]
</reasoning>

<answer>

Page B148b

No.	Problem	Answer
(10)	\(81 - 30\)	\(51\)
(11)	\(81 - 36\)	\(45\)
(12)	\(81 - 69\)	\(12\)
(13)	\(81 - 65\)	\(16\)
(14)	\(83 - 46\)	\(37\)
(15)	\(83 - 49\)	\(34\)
(16)	\(83 - 47\)	\(36\)
(17)	\(83 - 74\)	\(9\)
(18)	\(83 - 83\)	\(0\)

Page B149a

No.	Problem	Answer
(2)	\(73 - 26\)	\(47\)
(3)	\(73 - 35\)	\(38\)
(4)	\(73 - 37\)	\(36\)
(5)	\(85 - 46\)	\(39\)
(6)	\(85 - 53\)	\(32\)
(7)	\(85 - 55\)	\(30\)
(8)	\(85 - 77\)	\(8\)

</answer>

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

Answer:

<pre_analysis>
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]
}
</pre_analysis>

<reasoning>

Subtract values on page B148b

\[

$$\begin{aligned} (9) \quad 81 - 34 &= 47 \\ (10) \quad 81 - 30 &= 51 \\ (11) \quad 81 - 36 &= 45 \\ (12) \quad 81 - 69 &= 12 \\ (13) \quad 81 - 65 &= 16 \\ (14) \quad 83 - 46 &= 37 \\ (15) \quad 83 - 49 &= 34 \\ (16) \quad 83 - 47 &= 36 \\ (17) \quad 83 - 74 &= 9 \\ (18) \quad 83 - 83 &= 0 \end{aligned}$$

\]

Subtract values on page B149a

\[

$$\begin{aligned} (1) \quad 73 - 22 &= 51 \\ (2) \quad 73 - 26 &= 47 \\ (3) \quad 73 - 35 &= 38 \\ (4) \quad 73 - 37 &= 36 \\ (5) \quad 85 - 46 &= 39 \\ (6) \quad 85 - 53 &= 32 \\ (7) \quad 85 - 55 &= 30 \\ (8) \quad 85 - 77 &= 8 \end{aligned}$$

\]
</reasoning>

<answer>

Page B148b

No.	Problem	Answer
(10)	\(81 - 30\)	\(51\)
(11)	\(81 - 36\)	\(45\)
(12)	\(81 - 69\)	\(12\)
(13)	\(81 - 65\)	\(16\)
(14)	\(83 - 46\)	\(37\)
(15)	\(83 - 49\)	\(34\)
(16)	\(83 - 47\)	\(36\)
(17)	\(83 - 74\)	\(9\)
(18)	\(83 - 83\)	\(0\)

Page B149a

No.	Problem	Answer
(2)	\(73 - 26\)	\(47\)
(3)	\(73 - 35\)	\(38\)
(4)	\(73 - 37\)	\(36\)
(5)	\(85 - 46\)	\(39\)
(6)	\(85 - 53\)	\(32\)
(7)	\(85 - 55\)	\(30\)
(8)	\(85 - 77\)	\(8\)

</answer>

<post_analysis>
{
"subject": "Mathematics",
"question_type": "Free Response",
"knowledge_point": [
"Mathematics",
"Algebra",
"Column Subtraction"
]
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</post_analysis>