Free Geometry Book Download: Amsco’s Geometry

Free Geometry Book Download: Amsco’s Geometry Amsco’s Geometry is a comprehensive textbook custom designed for complete coverage of the New York State Core Curriculum for Geometry. Description     Geometry is a new text for high school geometry that continues the approach that has made Amsco a leader in presenting mathematics in a contemporary, integrated manner. Formal logic is presented as the foundation for geometric reasoning. A logical system of reasoning and proof is carefully built using appropriate language, postulates and theorems. Table of Contents     Essentials of Geometry     Logic     Proving Statements in Geometry     Congruence of Line Segments, Angles,...

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Free Geometry Book Download: The Geometry and Topology of Three-Manifolds

The Geometry and Topology of Three-Manifolds This is an electronic edition of the 1980 lecture notes distributed by Princeton University. It is available in pdf and postscript formats. Description     These notes (through p. 9.80) are based on my course at Princeton in 1978–79. Large portions were written by Bill Floyd and Steve Kerckhoff. Chapter 7, by John Milnor, is based on a lecture he gave in my course; the ghostwriter was Steve Kerckhoff. The notes are projected to continue at least through the next academic year. The intent is to describe the very strong connection between geometry and lowdimensional topology in a way which will be useful and accessible (with some effort) to graduate students and mathematicians working...

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Problem and Solution: Part 5 (Ratio Exercise problem and solution, Proportion Exercise problem and solution, Rate & Partnership Exercise problem and solution)

Question: 27 Coffee A normally costs $ 100 per 1b. It is mixed with coffee B, which normally cost $ 70 per 1b, to form a mixture that costs $ 88 per 1b. If there are 10 1bs of the mix, how many pounds of coffee A is used in the mixture? Option: (a) 4 (b) 5 (c) 6 (d) 7 (e) None Explore: Let, a be the amount of coffee A present in per 1b of the mixture. :. a x 100 + (1 - a)70 = 88 :. (100 - 70)a + 70 = 88 :. 30a = 18 :. a = 18/30 = 0.6 1b :. In 10 1b, we have 6 1b of coffee A Answer: (c) Question: 28 Two blends of tea costing $ 2.80 and $ 3.20 per kg, respectively, are mixed in the proportion 2:3. The mixture is sold at $ 4.80 per kg, What is the percentage of profit? Option: (a) 50.7 (b) 50.9 (c) 57.9 (d) 60 Explore: Let, tea of 1st...

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Divisibility Exercise problem and solution

Problem:   Is the number 621 prime or composite? Method:   In the last lesson, we learned to find all factors of a whole number to determine if it is prime or composite. We used the procedure listed below. To determine if a number is prime or composite, follow these steps: Find all factors of the number. If the number has only two factors, 1 and itself, then it is prime. If the number has more than two factors, then it is composite. (adsbygoogle = window.adsbygoogle || []).push({}); The above procedure works very well for small numbers. However, it would be time-consuming to find all factors of 621. Thus we need a better method...

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Problem and Solution: Part 4 (Ratio Exercise problem and solution, Proportion Exercise problem and solution, Rate & Partnership Exercise problem and solution)

Question: 22 The ratio of gold and silver in an ornament weighing 42 gm is 4:3. How much gold will need to be added for the ratio of gold and silver to be 5:3? Explore: The ratio of gold & silver = 4:3 Sum of the ratio = 4+3 = 7 The amount of gold = 42 gm x 4/7 = 24 gm The amount of silver = 42 gm x 3/7 = 18 gm Let, X gm gold will need to be added. According to the question, (24 +X ): 18 = 5:3 => (24+X)/18 = 5/3 => 72 + 3X = 90 => 3X = 90 - 72 = 18 => X = 18/3 = 6 Answer: 6 gm gold will need to be added Question: 23 The ratio of boys and girls in a class is 1:2 and the classroom has 24 students. How many boys would have to be admitted to make ratio of boys to girls 1:1? Option: (a) 6 (b) 8 (c) 10 (d) 12 (e) 14 Explore:...

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Problem and Solution: Part 3 (Ratio, Proportion, Rate & Partnership)

Question: 17 If Marie has twice as much money as Curie has, who has three times as much money as Sunny has. What is the ratio of the amount of money Sunny has to the amount of money Marie has?   Option: (a) 1:8 (b) 1:6 (c) 1:4 (d) 1:2 (e) 2:1 Explore : Let, Sunny hat $ X :. Curie has $ 3X :. Marie has $ (3X x 2) or $ 6X :. The ratio of amount of money Sunny has to the amount of money Marie has = X:6X = X/6X = 1/6 = 1:6 Answer: (b) Question: 18Masum has twice as much money as Selim and Selim has 50% more money than what Babal has. If the average money with them is $ 110, then determine the amount of Masum's Money. Explore: Let, Babal has $ X :. Selim has $ (X + X x 50%) = $ (X x 0.5%X) = $1.5X :. Masum has $ (1.5X x 2) = $3X According...

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Ratio, Proportion & Partnership: (part 2 )Exercise Problem & solved examples

Question: 10 Given (P + 7Q)/4P = 19/20, what is the ratio of Q:P? Option: (a) 1:2 (b) 1:3 (c) 2:4 (d) 2:5 (e) 2:7 Explore: (P + 7Q)/4P = 19/20 => 20P + 140Q = 76P => 140Q = 56P => P/Q = 140/56 = 5/2 => P:Q = 5:2 :. Q:P = 2:5 Answer: (d) Question: 11 Nine years ago the age of P and Q| were in the ratio of 2:3. After 7 years, the ratio of their age will be 3:4. What is the present age of P? Explore: Let 9 years ago the age of P and Q were 2x & 3x respectively. :. Present age of P = 2x + 9  Present age of Q = 3x + 9 According to the question, (2x +9+7):(3x+9+7) = 3:4 => (2x+16)/(3x+16) = 3/4 => 4(2x+16) = 3(3x +16) => 8x + 64 = 9x +48 => 9x-8x = 64 - 48 => x = 16 :. Present age of P = 2 x 16...

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Brain Waves Game

Instructions for Brain Waves Challenge your brain with 7 fun mini games. Read the instructions before every mini game. Wait for fully loaded, then click continue and then click continue and play. ...

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Ratio, Proportion & Partnership: Exercise Problem & solved examples

Question: 1 The ratio of 1/5 to 2/7 is: Option: (a) 3:5 (b) 5:7 (c) 7:9 (d) 7:10 (e) 3:7 Explore: The ratio of 1/6 to 2/7 = 1/5:2/7 = (1/5)/()2/7 = 1/5 x 7/2 = 7/10 = 7: 10 Answer: (d) Question: 2 The ratio of 1/4 to 3/5 is Option: (a) 1 to 3 (b) 3 to 20 (c) 5 to 12 (d) 3 to 4 (e) 5 to 5 Explore: 1/4 to 3/5 = 1/4:3/5 = (1/4)/(3/5) = 5/12 Answer: (c) Question: 3 A:B = 4:5, A:C = 10:9, then A:B:C = ? Option: (a) 4:5:9 (b) 4:5:10 (c) 8:9:10 (d) 8:9:10 (e) 20:25:18 Explore: A:B = 4:5 => B:A = 5:4 => B:A = 5:5 x 4:5 = 25:20 A:C = 10:9 => A:C = 10x2:9x2 = 20:18 :. B:A:C = 25:20:18 :. A:B:C = 20:25:18 Answer: (e) Question: 4 If A:B = 1:2, B:C = 4:3, & A+B+C = 450. What is the value of B? Explore: A:B = 1:2 = 1x2:2x2 = 2:4 B:C...

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