https://www.khanacademy.org/math/pre-algebra [2]
https://www.khanacademy.org/math/pre-algebra/negatives-absolute-value-pr... [3]
https://www.khanacademy.org/math/pre-algebra/factors-multiples [4]
https://www.khanacademy.org/math/pre-algebra/decimals-pre-alg [5]
https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg [6]
https://www.khanacademy.org/math/pre-algebra/rates-and-ratios [7]
https://www.khanacademy.org/math/pre-algebra/applying-math-reasoning-topic [8]
https://www.khanacademy.org/math/pre-algebra/exponents-radicals [9]
https://www.khanacademy.org/math/pre-algebra/order-of-operations [10]
https://www.khanacademy.org/math/pre-algebra/measurement [11]
Links
[1] https://hootsgo.org/?q=node/6268
[2] https://www.khanacademy.org/math/pre-algebra
[3] https://www.khanacademy.org/math/pre-algebra/negatives-absolute-value-pre-alg
[4] https://www.khanacademy.org/math/pre-algebra/factors-multiples
[5] https://www.khanacademy.org/math/pre-algebra/decimals-pre-alg
[6] https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg
[7] https://www.khanacademy.org/math/pre-algebra/rates-and-ratios
[8] https://www.khanacademy.org/math/pre-algebra/applying-math-reasoning-topic
[9] https://www.khanacademy.org/math/pre-algebra/exponents-radicals
[10] https://www.khanacademy.org/math/pre-algebra/order-of-operations
[11] https://www.khanacademy.org/math/pre-algebra/measurement