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Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

Factor -8x3-2x2-12x-3 by grouping what is the resulting expression?

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.