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Kyra went to the grocery store on Monday and bought 5 apples and 2 oranges for a total of $3.45. On Thursday she bought 3 oranges and 7 apples for a total of $4.90. What is the cost of apples and oranges?

Respuesta :

semsee45

Answer:

Apple = $0.55

Orange = $0.35

Step-by-step explanation:

Let A = cost of an apple

Let R = cost of an orange

Monday:  5A + 2R = 3.45

Thursday:  3R + 7A = 4.90

Rewrite 5A + 2R = 3.45 to make R the subject:

⇒ 2R = 3.45 - 5A

⇒ R = 1.725 - 2.5A

Substitute R = 1.725 - 2.5A into 3R + 7A = 4.90 and solve for A:

⇒ 3(1.725 - 2.5A) + 7A = 4.90

⇒ 5.175 - 0.5A = 4.90

⇒ 0.5A = 0.275

⇒ A = 0.55

Substitute found value for A into 5A + 2R = 3.45 and solve for R:

⇒ 5(0.55) + 2R = 3.45

⇒ 2.75 + 2R = 3.45

⇒ 2R = 0.7

⇒ R = 0.35

fieryanswererft

Answer:

apples cost $0.55 each, orange costs $0.35 each

Step-by-step explanation:

let apples be a, let the oranges be o

make equations:

  • 5a + 2o = $3.45 ............equation 1
  • 3o + 7a = $4.90 ............equation 2

make a the subject for equation 1:

[tex]\sf 5a + 2o = $3.45[/tex]

[tex]\sf 5a = 3.45 - 2o[/tex]

[tex]\sf a = \frac{3.45 - 2o}{5}[/tex]

solve:

[tex]3o + 7(\sf \frac{3.45 - 2o}{5}) = $4.90[/tex]

[tex]\sf 0.2o+4.83=4.9[/tex]

[tex]\sf o=0.35[/tex]

each orange cost $0.35

For apples:

[tex]\sf a = \frac{3.45 - 2o}{5}[/tex]

[tex]\sf a = \frac{3.45 - 2(0.35)}{5}[/tex]

[tex]a=0.55[/tex]

each apples cost $0.55

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