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MAria is 2 years older than edardo, and 3 years ago, Maria was twice as old as eduardo. Find teir present ages

User Yuxh
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Answer:

Maria's present age is 7

Eduardo's present age is 5

Explanation:

  • We can allow M to represent Maria's age and E to represent Eduardo's.
  • We'll need a system of equations to find the two ages.

Step 1: Find first equation:

  • We know that Marie is 2 years older than Eduardo.
  • Thus, our first equation is M = E + 2.

Step 2: Find second equation:

  • We further know that Maria was twice as old as Eduardo 3 years ago.
  • Thus, the other equation we can use is M = 2E -3.

Method to solve: Substitution:

Step 3: Isolate E in first equation:

(M = E + 2) - 2

M - 2 = E

Step 4: Substitute M - 2 for E in M = 2E - 3 (our second equation) to find M:

M = 2(M - 2) -3

M = 2M - 4 - 3

M = 2M - 7

-M = -7

M = 7

Step 5: Plug in 7 for M in M = E + 2 (our first equation) to find E:

7 = E + 2

5 = E

Thus, Maria's is 7 years old while Eduardo is 5 years old.

Checking first statement: Since Maria is 7 years old and Eduardo is 5 years old, she is indeed 2 years older than Eduardo.

Checking second statement: Three years ago, Maria was 4 as 7 - 3 = 4. Three years ago, Eduardo was2 since 5 - 3 is 2. Because 4 is twice 2, Maria was indeed twice as old as Eduardo three years ago.

User C S
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