Uget brainliest if answer correctlyfor question 1-2 estimate the sum or difference. use the bench marks 0 1/2 and 1 1. 23/40 - 11/30 2. simone measures the width of one cardboard strip as 1/2 yd. a second cardboard strip measures 5/6 yd in width estimate the combined width of the cardboard strips. for questions 3-4 find the exact sum or difference 3. 7/15 + 9/15 + 4/15 4. gerry spends 1/21 of her money on pencils and 2/21 on paper what fraction of money does she spend? give the answer in simplest form.

1. Okay well, 23/40 is close to 20/40, which is 1/2. Also, 11/30 is close to 10/30, which is 1/3. To subtract, we must have a common denominator, so multiply 1/2 by 3/3 and 1/3 by 2/2 so both have a denominator of 6. Then you have 3/6-1/6, so your answer is 2/6 which simplifies to 1/3. The best estimate for the answer is 1/3.

2. 5/6 is almost 6/6, which is one. So, the best estimate for the combined width of the cardboard strips is about 1.5 yards.

3. There's already a common denominator, so just add 7+9+4=20. 20/15 simplifies to 4/3 (if you divide by 5/5). The exact sum is 4/3.

4. 1/21+2/21=3/21 which simplifies to 1/7. Gerry spends 1/7 of her money.