Hey!
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~Cross Multiply
z/42 * 25/70 → 70z = 1050
~Divide 70 to both sides
70z/70 = 1050/70
~Simplify
z = 15
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Hence, the answer is [tex]\Large\boxed{\mathsf{z~=~15}}[/tex]
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Hope This Helped! Good Luck!
