Dan is twice as old as Bob. The sum of their ages seven years ago was 13. How old are they now?

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`x`²	`x`^□	log_□	√☐	^□√☐	≤	≥	□□	·	÷	`x`^◦	π
(☐)^′	`ddx`	∂∂`x`	∫	∫_□^□	lim	∑	∞	`θ`	(`f` ◦ `g`)	`f`(`x`)

☐²

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√☐

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log_□

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∞

∫

ddx

≥	≤	·	÷	`x`^◦	(☐)	\|☐\|	(`f` ◦ `g`)	`f`(`x`)	ln	`e`^☐
(☐)^′	∂∂`x`	∫_□^□	lim	∑	sin	cos	tan	cot	csc	sec

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Generated by AI

Dan is twice as old as Bob. The sum of their ages seven years ago was 13. How old are they now?

Solution

Bob′s age is: 9

Dan′s age is: 18

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Solution steps

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Translate the problem into an equation

Solve the equation

Find age

Bob′s age is: 9

Dan′s age is: 18

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−▭▭	<	7	8	9	÷	`AC`
+▭▭	>	4	5	6	×	☐☐☐
×▭▭	(	1	2	3	−	`x`
▭ \|▭	)	.	0	=	+	`y`

Dan is twice as old as Bob. The sum of their ages seven years ago was 13. How old are they now?

Solution

Solution steps

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