Manny used 8 tenth-size parts to model 8/10. ana used fewer parts to model an equivalent fraction. how does the size of a part in ana's model compare to the size of a tenth-size part? explain.

It should be bigger, think of a pie:
if you cut it into 2 parts, the pieces are big
if you cut it into 4 parts, the pieces are smaller

in both parts, the AMOUNT OF PIE stays the same, the size changes

here, we cut out 8 / 10 pieces, (manny)
ana has the same WHOLE amount, but in BIGGER pieces because she has an amount less than 8.

It works if you REDUCE THE FRACTION, 8/10 can be REDUCED to 4/5, Ana's pieces should be twice as big as Manny's, but she only has 4

Answer 20 centimeters15+8=2323-3=20so the answer is 20 centimeters

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