Prove or Disprove: for All Integers $$a , b , c , d \text {, if } a \mid b \text { and } c \mid d \text {, then } ( a c ) \mid ( b + d ) \text {. }$$

question 83

True/False

Prove or disprove: For all integers $$a , b , c , d \text {, if } a \mid b \text { and } c \mid d \text {, then } ( a c ) \mid ( b + d ) \text {. }$$

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Definitions:

Flynn Effect

The observed rise in average IQ scores over successive generations, attributed to environmental factors such as improved education and nutrition.

Industrialized Countries

Nations that have highly developed industries and infrastructure, often characterized by higher standards of living, technology use, and economic output.

Statistical Artefact

An apparent result or trend in data that does not accurately reflect the true situation, often due to methodological errors or biases.

Heritability of IQ

The proportion of variation in intelligence within a population that can be attributed to genetic factors, often discussed in the context of nature versus nurture debates.