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## Official Guide Explanations:Questions by Difficulty Level

Background

This directory links you to hundreds of free explanations I've created to the quantitative questions in The Official Guide for GMAT Review (12th ed.). There are lists of explanations sorted by question number, difficulty level, and content area. Question numbers beginning with a 'D' are from the book's Diagnostic Test.

I've also created explanations for the problems in the 2nd edition of the Official Guide for Quantitative Review.

These are the same explanations that are featured in my "Guides to the Official Guide" PDF booklets. However, because of the limitations of HTML and cross-browser compatibility, some mathematical concepts, such as fractions and roots, do not display as clearly online.

3 (Very Easy)
Problem Solving
1, 2, 5, 19, 20, 22, 25, 35, 37, 75, 77, 139
Data Sufficiency
3, 13, 22

4 (Moderately Easy)
Problem Solving
4, 6, 7, 8, 9, 10, 12, 13, 15, 16, 17, 18, 21, 26, 30, 32, 38, 40, 42, 43, 44, 45, 46, 47, 48, 52, 55, 56, 63, 64, 65, 71, 76, 78, 90, 91, 92, 94, 95, 96, 100, 118, 132, 133, 140, 141, 151, 153, D17, D19, D21
Data Sufficiency
1, 2, 5, 6, 7, 8, 9, 10, 11, 12, 15, 17, 18, 20, 23, 24, 32, 33, 37, 39, 43, 46, 47, 48, 49, 56, 57, 59, 60, 63, 64, 74, 81, 85, 86, 91, 107, 118, 119, 133, 136, 137, D26, D27, D35

5 (Moderate)
Problem Solving
3, 11, 14, 23, 24, 27, 29, 31, 33, 34, 36, 39, 41, 49, 50, 51, 53, 54, 57, 58, 59, 60, 61, 62, 67, 69, 70, 72, 73, 74, 79, 80, 81, 83, 84, 86, 87, 88, 93, 97, 98, 99, 101, 102, 105, 109, 111, 112, 113, 114, 115, 119, 120, 124, 125, 126, 128, 130, 131, 134, 135, 138, 143, 144, 150, 152, 154, 155, 156, 158, 159, 160, 162, 164, 165, 166, 168, 169, 171, 172, 175, 176, 179, 181, 183, 184, 186, 190, 195, 196, 199, 203, 205, 210, 222, D01, D02, D08, D12, D23
Data Sufficiency
4, 14, 19, 21, 25, 27, 28, 29, 30, 31, 34, 35, 38, 40, 41, 44, 50, 51, 52, 53, 54, 55, 58, 61, 62, 65, 66, 67, 69, 70, 71, 72, 73, 76, 77, 78, 80, 82, 83, 84, 88, 90, 93, 95, 96, 97, 100, 101, 102, 103, 104, 105, 106, 108, 110, 112, 113, 114, 116, 117, 122, 123, 126, 127, 129, 130, 131, 132, 134, 138, 141, 142, 143, 145, 146, 147, 148, 152, 155, 157, 158, 159, 167, 169, 174, D25, D28, D29, D34, D36, D37, D38, D40, D41, D42, D43, D44, D46, D47, D48

6 (Moderately Difficult)
Problem Solving
28, 66, 68, 82, 85, 89, 103, 104, 108, 110, 116, 117, 121, 122, 123, 127, 129, 136, 137, 142, 145, 147, 149, 157, 167, 170, 173, 174, 177, 178, 180, 185, 187, 192, 193, 194, 197, 198, 201, 202, 204, 207, 209, 211, 215, 216, 218, 219, 220, 221, 223, 224, 225, D04, D05, D06, D07, D09, D11, D15, D16, D18, D22
Data Sufficiency
16, 26, 36, 42, 45, 68, 75, 79, 87, 89, 92, 94, 98, 99, 111, 115, 121, 124, 125, 135, 139, 140, 144, 149, 150, 151, 153, 156, 160, 161, 162, 163, 166, 168, 171, 172, D30, D31, D32, D33, D39, D45

7 (Very Difficult)
Problem Solving
106, 107, 146, 148, 161, 163, 182, 188, 189, 191, 200, 206, 208, 212, 213, 214, 217, 226, 227, 228, 229, 230, D03, D10, D13, D14, D20, D24
Data Sufficiency
109, 120, 128, 154, 164, 165, 170, 173

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